Not sure how large the holes are, but you could try some plastic dowel inserts.

https://www.amazon.com/PSCCO-Plastic-Inserts-Mounting-Screws/dp/B088QWWB4F/ref=sr_1_8?keywords=plastic+dowels&qid=1648762474&sprefix=plastic+dow%2Caps%2C136&sr=8-8