I don't think it is a Sim glitch...
After inserting the "eng fail" fault,the FADEC will attempt a restart (eng master sw still ON), but due to low aircraft speed, the FADEC will use the starter motor and thus asks for X-Bleed.
You will not get "start valve fault" if APU is supplying the bleed sys.
If "eng fail" is inserted at hi spd (say 300 kts) windmilling start will be selected by FADEC and you will not get "start valve fault".....
IMHO if the "eng master sw" is selected off w/o delay after inserting the fault, then you will not get the starter fault...
Thanks