I was checking to see how a 3/4" dog hole would look in a vise jaw made from two 3/4" pieces of plywood. Just clamped for the test, but would be glue for the real thing. Interesting to see the hole opened up. And luckily no splitting, but do you think it would work as an actual vise jaw? This is for a Veritas quick release front vise, so the jaw is only supported in the middle.
Paul Sellers has been known to use plywood jaws in years past, but he is using some nice stuff with a lot of void-free plies, and he is not putting dogholes in it. Honestly, though, even the material you have there, if laminated to 1.5" and with just one or two 3/4" dog holes, it should work pretty well and would be easy to replace. If you are on a budget but want to do hardwood, this is a perfect job for red oak.