Jiraya cannot win this. There is clear gap in portrayal between the two.
Obito hype is out of all proportion to Jiraya's... Jiraya hype is very good, he is a Sannin well known and respected around the world (especially in P1 with the Itachi/Kisame scene) but...reminder it's cuz 14 years old Obito Minato sealed Kyuubi in Naruto. It's the genesis of the manga.
Even Jiraya was worried about the masked man
Everyone thinks it's Madara, but it's Obito, the leader of Akatsuki, who's freaking them all out. And it's because he's Madara's disciple and he's managed to get Obito to replace him.
Post-tnj Obito did say that Jiraya defeated him. But it's clear that it was ideologically.
Otherwise to get back to the fight:
Base Jiraya and even SM Jiraya will never be able to land a hit on Obito.
Even A4 fail to do that.
And we know Obito was able to hold on and troll against KCM/BM Naruto (the one that can dodge V2 A4), Hachibi and WA masters (and among them there is Kakashi that have the perfect counter to Obito Kamui) between chapters 595 and 598. And he just using
his Kamui and 0 Rinnegan jutsu. Even the Mazo wasn't used here since Obito was forced to protect him (an additional constraint).
And Rinnegan wasn't necessarily a real advantage
since Obito almost lost himself cuz the power of this eye. And too much power can swallow you up and devour you. Just look at Madara that exploded when Black Zetsu filled him with the chakra of the victims of Mugen Tsukiyomi.
So I think MS Obito won't have any problem against Jiraya (he had problems against Konan because she had spent years preparing the perfect anti-Kamui trap. And against Torune, he lost his arm because of his special ability of nano-insects but it didn't seem to bother Obito).
Jiraya may be much more versatile, but he's no match for Kamui's hax who can bypass everything Jiraya has to offer (even jutsu like the Yomi Numa or the one from the stomach of the toad that almost trapped Itachi/Kisame. Same with gamayu endan ect...).
Obito could possibly even troll him with a powerful genjutsu (Obito is indeed the one who hypnotized Yagura the perfect Jinchuuriki). At worst he will take control of the summons (Gamas).
He also has a very large jutsu (at least as powerful as the most powerful jutsu of SM Jiraya).
I doubt Jiraya can even activate the Sennin mode under such pressure from Obito who will be able to bypass all his defenses (Gama and co) via Kamui. Even KCM Naruto had been put under pressure by Obito and got away with it only thanks to the WA masters.
And even if he does, he'll still be under a lot of pressure (even though he gonna do better and he's got the wise toads on his shoulders.). He can be absorbed by Kamui at any moment (and Kamui still bypass his attacks like senpo goemon) and being a sensor won't necessarily help you spot immaterial Obito any better. Fuu couldn't detect him when he dematerialized and hid in matter to better attack by surprise. Jiraya will really have to be very, very reactive to avoid vicious attacks.
There's just the frog song that might work and I still doubt it since for me it would be enough for Obito to dematerialize his eardrums to avoid sound attacks. And the genjutsu also takes time to activate.
And once again, even if Jiraya managed to throw it, Obito has his ultimate trump card Izanagi. Perfect for trolling Jiraya in the back, just like with Konan.
Knowing that SM Jiraya had been trolled by Ashura Path after he thought he beat Pain with the frog song
It will be worst with Obito.
I really don't see how Jiraya can counter Kamui. He just has the manga knowledge here (Obito also has just manga knowledge but as leader of the Akatsuki Obito must have a lot of information about Jiraya. The reciprocal is not valid even if Jiraya has a spy network, he just felt uncomfortable about Obito/Madara possible existence. He can't have much knowledge.). It'll take him time to understand everything and he'll get beaten up before (that's also why he got killed against Pain. He was looking for his secret).
Sending Obito to a toad world would probably not work since Obito could teleport to escape (he was even able to reach Kamui from Kaguya's dimensions).
There is very little chance that he could pull off a miracle strategy to hit/kill Obito before the toad absorbs him.
It is impossible to get him up to speed (Minato (>>>Jiraya in speed) barely managed to do so against teen Obito. With a thousandth of a second to go it was Minato the defeated one).
The best strategy for me is with full knowledge, to send clone sensors very powerful in Kamui. Knowing that when Obito teleports a target into Kamui, it doesn't normally appear close to the part of his own body that he sends into Kamui to defend himself. We see this in the case of Fuu/Torune.
Obito sends Torune into Kamui and then
dematerializes just afterwards in front of Fuu. But yet Torune did not attack Obito from Kamui. This means that Obito can send his victim anywhere he wants into the other dimension (that's why he's so confident in his Kamui even against multiple enemies). Also why Sasuke/Karin were not in the same place as Fuu/Torune in Kamui). So with full knowledge, you'd have to send sensor clones able to detect where parts of Obito's body are in the dimension.
I don't see SM Jiraya capable of such a feat (he's not a cloning spammer).
And if Jiraya (the original) gets absorbed into Kamui. No, reverse summoning won't save him. Already he won't be able to come back on the battlefield by himself (Suigetsu had summon Sasuke after this one had fled Deidara with Manda in the kingdom of the snakes. Jiraya will surely land at Mount Myobukou).
And I don't even think Jiraya can summon a toad in Kamui.
Sasuke, prisoner in Kamui with Karin, couldn't get out (even though he had those summons) and asked Obito to get him out.
As a result, it's impossible to escape.
Obito is too big a chunk for Jiraya whose only advantage is versatility. Even in endurance it shouldn't be better since Obito has Hashirama cells (and Obito fight literraly 24 hours during the war. He also have an incredible will but here it's not an advantage. Jiraya also has an incredible will when we saw him stand up one last time against Pain).
And it's even possible that
MS Obito can use Gedo Mazo.
So sorry about Jiraya but MS Obito is much stronger.
Obito low diff (mid diff in the worst case but it's very unlikely).
