Where is the stain? Is in the middle or by a seam. You may be able to get it repaired, but the extent of the repair depends on where the stain is. I know you said you tried rubbing alcohol, but have your tried a mr. clean magic eraser. I haven’t gotten so many stains out that I thought were hopeless with this. Good luck

Try some off that new Goof Off cleaner. It takes dried acrylic paint off really well. There is another one called OOPS! that isn’t quite as thorough as the Goof Off but it does work. I’ve used the OOPS! to remove red drink stains from a white hoodie and it did take 90% of a blue permanent marker stain off our dark spruce green sofa.

ALWAYS test on a hidden spot before using it on the stain. See if it causes any damage, color change before proceeding. Will warn you; both products smell more than a little nasty; use good ventilation. The advantage with the leather is that the stain remains on the surface and doesn’t get down in the fibers.

I’d hesitate to use the eraser sponges; they are abrasive and are liable to scratch or remove the gloss from your leather. But you will probably have to apply a dressing made for leather to any of the solutions and that should be part of your maintenance on the sofa to keep the leather soft and supple and less prone to cracks and dirt settling into the leather.