The Sungod lore and connection with Elbaph could be a good indication that Urouge could be involved; but it is never certain.
Another interesting thing was in SBS Volume 95 when Oda answered what Flowers some characters would represent. He chose a Daisy for Urouge.
The meaning of a daisy flower can be purity, innocence, new beginnings, joy and cheerfulness.
I don't know if we should look too much into this, but thematically it would fit.
Now, there are also voices that want Urouge to be involved with Enel, because we still don't know Birka which Enel destroyed, was his homeland or not. I think we will learn more once we explore the highest part of Elbaph, the Heaven Realm.
There is still that other route to Sky Island which we haven't seen yet. Ganfall mentioned back in Skypea, the entrance via High West. Maybe it was Elbaph after all.
(I don't think hes the underling of anyone, he seems to do his own thing). After he attacked Snack, one of the Big Mom Pirates he retreated to another Sky Island ( Balloon Terminal to heal).