DH and I just returned. The current shuttle between Jambo and Kidani is not handicapped accessible. There are at least three steps up into the vehicle. There was not a WC lift like you see on the regular buses. That is not to say they could not call one up. This is actually a good question. Like the PPs it would probably be easier in good weather to just use her chair over there and back. The vehicle between the two used to be a van, now it is a much nicer small shuttle bus, that seats about 12, and people can stand. There are screens at the bus stop that let you know how long the waits are for park buses.
If using her chair, I would be sure to ask for the fastest route between the two...like if staying at Kidani...is there a door at the far end closest to Jambo to exit making it a closer trip for her....rather than out the front door. Seems like when we walked before, we used an elevator to get us down to parking garage then could walk over.