Don't want to give false hopes. But it looks like your friend
intends to be a RSAF pilot. In which case, the "powers at the top"
may view things differently.
But firstly on the personal front, how bad is his injury? This will
be the most important question that will be asked by any selection
panel. Will he recover within the next few weeks???
I would suggest the following:-
1) ask him to sound out and convince his current BMT OC (not PC).
The OC's recommendation is important, be it to OCS or SISPEC, as I
remember. He should try to get into SISPEC at least ( I believe
this is the minimum nowadays to get into the RSAF review
panel).
2) Go get some MO advice on therapy and make sure that his current
weakness of his arm is on "official record". Assuming his other
personal factors are good, e.g. his attitude, his other BMT test
(marksmanship) etc etc , I think because he is aiming for RSAF
selection, he stands a good chance. Maybe wrong but I was part of
the system years ago and I believe the mindset is still the
same.