i highly suggest you to seek Immigration Lawyer's advice rather than seeking here.
since PGP is a lottery and she has been selected, and at the same time her hearing is in next month, if you decide to submit PGP application, IRCC may put it on hold or refuse it until her asylum status is resolved. however if you ignore it, you lose this rare chance.
I would suggest you to submit the PGP application to keep her spot. at the same time, let her asylum case continue. do not withdraw asylum. it could leave her without status if PGP doesn’t work out.