Yes, the base formulae for the @steem-ua curation rounds is as follows:
Step 1:
UA_Vote = x * UA_Account + y * UA_Post + z * UA_Comment
where
UA_Post = sum(VS * UA_Voter)
Step 2:
All posts UA_Vote scores in the same curation round / window are than compared relative to eachother, and then those relative scores are voted on percentage-wise.
So indeed, it depends on who comments / engages on a post, which is in this case quite some high-UA accounts (not just witnesses though!)
And arguably, favoring high-UA commenters makes sense: