I don't think the "Cass will be ok" part of your post is what people are taking issue with as much as it is your rationale for Parris being an alleged underdog in this match. If you watched Parris closely last year, you'd understand that large heavies with even just a moderate amount of skill and health gave him fits because he would gas trying to (a) shoot legs and then have to get out from beneath the subsequent sprawl, and (b) escape
from bottom during mat wrestling.
1-legged Stoll or 2-legged Stoll, Parris
typically wasn't beating that kind of guy unless he could (a) throw him for a TD and (b) avoid being on bottom more than a minute in the match. Neither was happening at his stage of development last year. However, this year's version of Parris would be a totally different story. So it doesn't make sense to say Cass will be ok vs. Parris simply because of the latter's performance vs. Stoll last year; his problems of last year appear to have been resolved.
If Cass will be ok, it is because he is really good, and just a bit better than Parris, who is also really good. I expect it to be close, perhaps coming down to RT. Cass will need to be sharp on his feet, though.