Is pulling current from Collector to Base allowed? (PNP transistor)
yes, that's allowed. no harm will be caused to the transistor.

Note than when you have the switch switched to ground you effectively have two IK resistors pulling down on the zener. both R1 and R2 will take zener current.

Also C2 might be better placed in parallel with D1 than with R2 so that when powere iz connected the pmos gates doesn't see a spike of full voltage.