Lol you can suck on the Part 1 Portrayal, it doesn't help your argument when Kisame later is handpicked by Obito to join the Akatsuki, later told he's strong enough to be partnered with Itachi by Yamato (who's only reference is Kakuzu), who has Perfect Jinchuuriki levels of confirmed hype and fights solo against a perfect jinchuuriki when the Akatsuki are meant to take on incomplete Jin.'s with teams.
Hell, he even took on a semi-perfect 4 tails that could use TBB by himself.
Toshi please reread the manga before saying this shit lol, Kakuzu is literally two meters in front of Kakuzu with all his hearts at close range. Kakashi's Kamui is 100% hitting and taking out Kakuzu at this moment. Even if the first isn't, nothing prevents Kakashi from using a second to finish Kakuzu off.
Likewise if he were to just kamui away the attack, he'd have needed to act before it was used. He cannot Kamui away the big ballooning fire bomb, his skills with the mangkeyou sharingan are pretty subpar until the Pain Arc and we don't see him attempt anything this big until the Gedo Statue circa #595.
Something this large is impossible for Kakashi to take down and it's not like he can place Kamui right in front of the attack's path, it's going to expand in nearly all directions like the panel shows.
Kakashi even acts nonchalant about Kakuzu not forcing him to use the mangkeyou sharingan lol