paypal refund after gcash conversion?

My sister sold something in Facebook almost a day ago and the transaction went pretty well without any problems. But just around 11pm she found a post that the person she sold her stuff was just outed as a scammer.

She's worried na baka yung buyer daw mag file ng refund and cause problems pero she already converted the money from usd to php and already transferred to her gcash and spent it on food.

Would it still be possible for the buyer to ask for a refund on PayPal (buyer uses usd) Or are the chances low since it's already gone? Thank you! Will take down if not in appropriate group to ask ^{^} Just want to give her a piece of mind