It doesn't look like the OP was dealing with Naster but with some third party. Not sure what's the connection there. Was Naster the recipient of the bitcoins in exchange for those PayPal funds? If so then Naster should pay back the full $725 ("someone else scammed me" is not a valid excuse).
You posted only one screenshot, but you didnt post the screenshot where we decided that I should refund 300 USD to your account what I did. I didnt send you paypal, one customer sent you (and you allowed that!) and he scammed us.