I would agree with you. If heaven contains everything good, everything our hearts could desire, all the love we have known and the presence of those who have loved us; would there be a huge hole there if our closest companions were excluded?
To paraphrase from that show, “If my dog ain’t welcome, then I suppose I will just find somewhere else”.
Yes. If I got there and found there was no place for my critter, I’d do what the old man did - move along and find someplace better.
I’m sure that somewhere in those ‘many mansions’ the Lord made a place for those of us who have loved our animals.