I believe your slides are electric, as are mine and my parents (2006 Simba Gas). The slides will not operate with the ignition key on or engine running. I suspect with you engine off your battery is too dead to run the slides also.
You should be able to check the flashing light code on the generator to point you in the right direction. You may need the manual for this as there are many codes and two phases to the flashing codes. I would suspect a gummed up carb as initial stalling is a common symptom. I think the code for fuel delivery problem is 33, but check your manual for how to read the codes.