im in the same situation as you cant seem to get any accelerators to actually work cant double spend and cant cpfp. let me know if you have any luck or figure anything out im at 17 days now.

 im wondering if by doing the rebroadcast and accelerate process it actually kept updating the transaction in the mempool meaning it technically is active which according to that it would mean we would have to sit and not touch the transaction at all for XXX so many days before it truly timed out..... i dunno its about the only theory i have left.