My biggest concern in the VinJo-ZacJo matchup is whether VinJo can go the full 7 minutes at an attacking pace against ZacJo's very physical style. I could see VinJo getting an early lead via a TD in the 1st (hard to see a whole lot of scoring in the 1st as good defensively as Jordan is), but I'm not sure he's going to be able to make it "stand-up" for the full 7 minutes. Would have to go with Jordan as having the bigger "tank" and that is the biggest concern imho especially given Jordan's physicality.
In regards to Nevills v Medberry, I just see this as a very close match - pretty much a tossup - based on results against common opponents to-date this year. They've both earned their Top 4 ranking on the mat - in terms of Ty Walz and Medberry being in front of Nick in the rankings this year, it really is not based on anything that has happened this year....imho, it's completely based on Medberry AA'ing in 2015 (took an Olympic RS last year) and Walz AA'ing last year. Would not be surprised if Nick won this bout based on performances against common opponents as Nick's offense has really been coming on and most big HWTs (Medberry is a 285 maxer) struggle defending against Nick's "neutral offense". Nick really does have a "varied attack" from his feet for a HWT (i.e., quite the opposite of a "dancing bear").
