Okay. . .I didn’t really care enough about this to look earlier on, but now that some fussing has started over it I’ve gone ahead and done an online search for every relevant combination I could think of involving the words “wolverine”, “hammer”, “inflatable”, “rinco”, and “toy”. And yes, I got some very. . .ummm. . .interesting results.
But what I found: I could only find one example of the Wolverine inflatable hammers that wasn’t just a recap of this story.
It included this image:
So the item seems to exist. But the image is too small on that page to see if the placement of the valve is where it has been claimed. . .though it would make sense to have the valve in that part of the toy. On the ones in the Mike Mozart video, the valve seems to be on the side that is presented in the above photo. Though it’s hard to tell because of the extremely irritating way he has of shoving his face or the toy right up into the camera lens so you can never really see the whole thing.
Here is another webpage that sells similar products (such as the Spyro the Dragon inflatable hammer, whomever he is). At the bottom of the page it states “RINCO = Really Inexpensive Novelty Company!”
So it seems to be the same company making that inflatable hammer as Mike Mozart said made the Wolverine one. Again, though, I’m not seeing the placement of the valve anywhere on the product, even though the picture quality is better on this website.
Finally, here’s another page that lists several other inflatable superhero hammers for sale. They only have them with Hulk, Iron Man or Spider-Man on them, but Marvel Comics seems to indeed have had a line of these toys. There’s no information on who made it. And it’s still not clear where the valve on them is.
So it seems that there is indeed likely a Wolverine-themed inflatable hammer. But the positioning of the valve is still in doubt.
EDIT: And here’s a website with one of the Spiderman hammers as well as a Green Goblin one. It shows the reverse side of the Goblin one than is shown on all the other hammers. No sign of the valve’s position on it, though.