currently the only way to set a bounty by using this link

what ever happened to the link in the shop section?

I think no one used the bounties and there for it was removed and I think the bounties from that link will be removed soon enough too

Bounties were broken for quite a while and they might have gotten broken again, or devs might have decided to simply discontinue them for some reason.

Sir would have an answer to your question if you manage to get in touch with him.