Not necessarily. It could be an indication that Thorne has let them know he's not interested in staying on for another year.
In fact, Loren Tate recently mentioned the staff is feeling more certain of the 6th year if they do go that way.
It is a tough decision & not sure it can't be a combination of willingness to leave and chances on a waiver.
...Where is Thorne's view of the risk/reward?...even if it is 90% he gets the waiver, there is still a 10% chance you sit out, then lose the waiver along with an opportunity to make a last impression or at least show your healthy again before you try to turn pro.
...How much does he really need to do to improve his stock professionally. Assume foreign leagues also look for potential like the NBA, so maybe he doesn't need to be all the way back to game form, he put up good numbers when healthy, maybe just showing he is healthy & improving and letting teams extrapolate on where he ends up doesn't hurt his status...finishing the season now with 14ppg/8 rpg (or whatever number you want to make up) but trending upward might look better than 14/8 consistant across the year.
...taking a struggling B1G team that even our Koolaid crowd thinks is good for about 6 wins & getting them to the tournament would look pretty good on his resume as well.
...Is he ready/confident he can put up good enough numbers then there is an opportunity, if he isn't i think it is probably in his best interest to try to come back...but even that is extrapolation on how he will feel in a month or so, more than how he feels today.
...all I know about 6th year waiver I've read here, but sounded like you need to return if you are capable, it could be a stretch, but maybe making a good faith or the appearance of a good faith effort helps your case on the waiver as well.
Add to that that you delay a paycheck another year & it is a tough call for anything less than 100%. comeback for appearance sake? Tough spot for the kid