Comment “like” problem – “users who like this” avatar linking to current user profile instead of “liker’s” profile

I can’t give more than a partial answer here, since the details might depend on the peculiarities of your theme and installation, including UM and how you’re using it.

Without installing and cracking open UM, too, I’m not sure I could figure out why you’re getting the unexpected results you’re getting. However, if you want to hack the setup, you might go to the get_liked_users function you’ve provided above, in class-ulike.php, lines 430 – 450 (or possibly add a filter there), and either create your own token to go with the the ones shown and available on the settings page, or re-write one of the ones already provided, adding the details, including the link to whatever profile or bio or author page, etc., you want, and as you want it. Any set of links you need should be easily derived from $user_info in one way or another, since it relies on get_userdata()