Hard to tell, but...
It sounds like the system is supposed to provide assistance to let the astronauts sort stuff out for themselves. The head-mounted display is presumably for the use of a non-expert, and tells its wearer what they should be sticking where. Talk of 'ultrasound probes' sounds like it is intended to deal with diagnosis rather than be a My First Open Heart Surgery system... even with a 40+ minute round trip, the operator would presumably be guided through all the necessary steps to gather the information the real medics back on earth need to know in order to provide useful advice.
Basic surgery isn't rocket science; you can train up almost anyone to do stitching, bone setting, casting, whatever. Diagnosis is potentially much harder, hence the need for this sort of system.
Course, I might have the wrong end of the stick entirely.