When all else fails, I either give up on the fabric or try a round of heat treating. With a pyrex or large microwavable (preferably glass) bowl, dampen fabric first and then immerse in water. (Edit -- if using plastic I would not use for food use after dying use) Wrap the top well with plastic wrap, and nuke at high for 20 minutes...then I let it cool down until I can touch it, do a rinse (maybe with a small amount of original dawn) and that doesn't work -- time to move on!
I think this was the thread and someone was talking about red flannel. Not only does it often bleed excessively, but it also "crocks" that is, rubs off on other fabric. If you have any long term in your stash, I suggest wrapping it in tissue paper.
This picture is of a fabric I gave up on. Both patterns were released at the same time/same line and I used a blue with no problem. I did a standard pre-wash but no color captures, or tests, and it was the one time I ruined a quilt with bad fabric. Turned the sophisticated silver grey/blue/white/maroon into baby pink
So the dark piece has been washed a couple of times before I stopped. The Orange piece started out the same color and after 7 or so washes, still runs like a thief in the night...