It is indeed.
Take the raw Hulk 181 me and Dave looked at. We ask the dealer if the book has the Marvel value Stamp and he said yes. Flip to the page and yes it has a MVS, but the wrong one. What someone had done is swap out the wrap from a Hulk 179 in place of the wrap from the Hulk 181.
Knowledge helped in this. As I collect Marvel value Stamps I instantly knew it was the wrong stamp in the book.
Later the same dealer tried to trade the tainted Hulk 181 to a friend of mine for his WWBN 32. The friend came to me and asked my opinion of the potential trade, and I asked who the dealer was. He told me, and then
To the OP, mind sharing a scan of the book? That way those of us who are chiming in can see if the outside looks 9.4 9.6, and then the issue is an interior problem which many would miss.