90 days is all the Starliner can do in space, and that's if everything's working right. Boeing's in a bind -- they want the ground tests to verify that it's safe to fly, but instead the ground tests have only identified the problems, and these are all things that should have been figured out during engineering and development.
If they send the craft down with a crew in it, there's a good likelihood that the crew will die in one or more of the failures, and the scuttlebutt is that manual or partially manual reentry will no longer be an option.
If they send the craft back to Earth uncrewed and it fails (as seems likely) NASA will have to suspend the contract for the crewed flights until the craft (already delayed a few years) has its bugs ironed out.
If uncrewed automated landing (propulsive, on land) actually succeeds, sending the crew down in a different craft -- by a competitor -- will have been the right move but make them look like they can't get the job done.
Of course, if they send the crew aboard Starliner for return to Earth and it works, it will look more like gambling with their lives than it will look like a success.
They are stuck between a rock and a empty space..............