Are we talking about the HPSP scholarship, or something else?
May be there's a way to obtain a similar scholarship without being commissioned, because citizenship is required to be commissioned to become an officer.
Some time ago there was a pilot program that allowed non-citizens to join with some commitment and then they'd be eligible for citizenship very quickly (I think it was something like a year). As I understand, that pilot program is currently on hold for a moment for "evaluation." I am not sure when they'll start it again.