If you're on an MPL course when the airline goes bust, seek advice from the flight school about your best route for continuing. That'd likely be transitioning to a CPL/ME/IR should you not be that far into the training.
With regards to an MPL itself I believe that the value of several simulators in your eventual type seriously can't be understated. Despite taking the CPL route, the typical type rating is only about 10 simulators + your line skills test. That's not a huge deal of time. The success of an MPL with respect of stick and rudder depends entirely on the syllabus the airline asks the schools to follow as some airlines modify the syllabi to their needs more than others.
But to get back on track, as I understand it an MPL licence holder can still have add new ratings so it's simply down to an airline to accept an MPL licence holder. I'm happy to be corrected if need be.