Nope its confirmed due to Momo's flame Breath not Yamato's trash AdvCoC.
Trash adv conq haki? Lol That trash adv conq haki is what greenbull acknowledged as strong haki(remeber he is an admiral and at his stage acknolwedging a user as strong haki is very rare where he didn't give a damn about king and queen). Also only that attack he felt pain.So damn you the haki still rocks