I really don't want false hope, but I think the doom and gloom train is a little ahead of reality. Could they be right? Of course! However, I think the "it's been 20 months" line lacks nuance.
The ACL, as far as we know, went fine. Bhak has then had 2 (or 3?) follow procedures for the same knee, but it wasn't on the ACL. Should we be happy that he's needed those follow up procedures? Pretty sure no. Are they good news? Also no.
What those follow ups do, in my mind is reset the clock. Depending on when the most recent work was done (and what that work was, we do not know) he might be on a perfectly normal recovery timeline.
In my head, I equate these secondary acts like technical troubleshooting. The Doctors fixed the ACL and now we've found a new problem. Fix that one and another pops up. There is value in a new, different error message. (Please tell me someone else works in IT/software.)