I'm not sure what you're arguing. Yes, it's possible that all this leads to is being another ally. The same thing could be said about Yamato who you seem to be rooting for and who is helping Momo a lot more than Luffy right now.
What Carrot has more of is actual camaraderie with the crew. She's bonded with Chopper, Nami, Sanji, Brook and Jinbe, and the moment that made me realize she has a shot was when Pedro died and Luffy called for her help along with the rest of his crew, even after she got pummeled by Katakuri. Luffy does trust her and know who she is, and she has a chance to seal the deal, chance being the key word here.
Yamato, by comparison, has only spoken to Luffy and Franky, and they barely know who he is. Luffy obviously trusts Yamato anyway, just like he immediately trusted Drake and even lousy Caribou. Yamato has strong points over Carrot, certainly. But if you're gonna make the Grand Fleet argument against Carrot, it's just as strong a case against Yamato as well.