Stall and surge are synonymous, for all practical purposes; GE/CFMI like to use "stall", PW & RR "surge". Very loud bang, increasing EGT, maybe N1/N2 rollback. May or may not incur severe damage, which would be indicated by an inability to recover.
(Note for the record: I was once called to respond to a pilot's writeup of "flameout with increasing EGT". It was, of course, a stall) (I am not making this up...)
Separation would be indicated by a bunch of zeroes, and an intercom call from the F/A.