Bug bounty? (Paying someone to fix an Arduino bug)

There's a bug in the Arduino compiler that's causing me headaches. It was reported years ago, has been labeled as a toolchain bug and assigned to someone to fix.

The bug was in AVR C but a patch was generated and the fix was committed in April 2015.

I don't have much, but I'd be willing to chip in some money for a few hours of someone's time to get this fix int the Arduino code. Since Arduino is open source I'm not sure how or if this is done. Should I directly contact the person to whom the bug was assigned or is there another mechanism?

Arduino is on bountysource
they did solve one issue on there but only one so I'm not sure if it is worth trying that but it is a preexisting mechanism for offering a bounty.