These discussions stemmed from a thread that was 2 years ( Refunded Files able to download even after refund approved. ) old which I locked yesterday. This was a bug when the refund system was introduced, but has LONG since been resolved.
To put things simply NO. The moment you click the “Accept Refund” button that option is gone! 
If you ever have doubts about a system on Envato, just contact Envato Authors Help and Support instead of resurrecting old threads for issues that were solved and causing unwanted panic for everyone! 
With this being said, no, buyers can’t download anything after the refund has been approved.