The mini is dumping the fuel, not refunding (un altered config). All other fuel vehicles ive tested refund. Current Plug, Rust and Oxide version, one fresh DL and install, one server restart, no change. Anyone else had this?

OK, heres the deal, it was self inflicted, heres the findings so that it may help you, should you exp the same issue.
I'm also using "Mini Copter Options" for the storage box and spotlight. in that config is this option.

 "Drop Storage Loot On Death": true,​

It must be set to false for the refund to work properly.