But now the zig project are responsible for denying someone else $5,000. I think that's unfair pressure to put on them. It may also cause some of the potential bounty claimants to exert pressure on the zig team too.

This is not true.

The $5,000 reward did not required the work to be merged upstream. Please read the rest of the thread

If you want the work done, why not just pay someone to do it instead of playing games with bounties?

Couldn't he just put it in a roadmap to be reviewed, merge the work if acceptable, accept the reward himself, and reward Zig team accordingly by other means?