This '97 model has an electronically controlled transmission and it has
a "2nd gear limp home mode". That's where your car is now.
My '97 (gas version) has a red cap on its transmission filler that I've
never opened - if there's a dip stick attached I'd at least try to check
the fluid level, also look at the transmission for leaks and pan damage.
Otherwise, you're at the mercy of the stealer - suggest you ask for a
"Diagnosis and repair estimate" ONLY and then decide the next step.
Make them come up with a reason for the problem and a cost to fix that