If you have a working patch for this that makes it a configurable option then just use that. There is no harm in submitting that as a merge request either, worst case it gets rejected again and you're in the same spot you are now. I don't believe a real non-intrusive patch was ever submitted for this, everything out there just seems to be a revert back to some old functionality that breaks other things. (Please don't waste maintainer time submitting patches that are broken or hacky, or patches that were already rejected. When in doubt talk about it with them first before submitting anything, and make sure your patch is actually new and addresses all the concerns that were made in the bug tracker already)

If it does get rejected then you do the same thing you'd do with any other open source project: convince your distro to carry the patch. I think the key here is to just not lose sight of the goal which is to get enough support somewhere to have the patch maintained, if you don't care to become an upstream developer and work closely with them then you can skip that and just do the same process but only with a downstream that is relevant to you.

If the patch still needs a lot of work/money to get it to the point where it's stable and doesn't break other things, well, now you know why upstream doesn't want to do it... so with that I would say a way to help would be to commit to maintaining this for however many years you expect to be using the patch. I can't give you a specific quote (I don't have any interest in working on this, sorry) but based on average developer rates you probably should expect to spend at least a few thousand dollars on this total, over several years of maintenance time, if you are not the one who is going to be writing the code. Of course, you can reduce the burden on yourself by getting a distro to share the cost, which is why I suggested that first :)