Say you Instant Fusion a lvl 5 or lower fusion monster (that can be fusion summoned by Instant Fusion) and then tribute him for a LVL 5+ monster and then bring him back with Premature Burial or Call of the Haunted... I would think the effect of Instant Fusion that destroys him in the End Phase resolves without effect since he has already gone to the Graveyard. Is that correct thinking?