Revat, thank you for the suggestion. Bird, thank you for your opinion on these.
Looking at the ones on eBay, it seems like most of the current signature series signed comics for sale are signed with the signature style that looks more like "Migma". I have seen others in previous research that look more like what I have here though as well. Here's one I found for an example: https://images.app.goo.gl/XocBEShPNtmymk8h6.
Research tells me that he has done signatures in a couple of different ways. I'm not sure if that has changed over a period of time, or if it's just some different ways he does it. Either way I'll keep researching the official signature series ones to compare, and I appreciate the help!
Oh and here is one currently on eBay in the other style. It's quite a bit different, actually. https://i.ebayimg.com/images/g/WPgAAOSwJ4xeh8d3/s-l1600.jpg