Acrylic paint staining

Acrylic paint that was being used on a canvas got spilled. Lady used Goo Off to clean the large spill. Said it looked clean when wet, now once dry you can see the bid blue hue. Looks to have stained the concrete. They think the concrete is about two years old, which could have its own issues. Read the few posted about acrylic paint removal, but this seem to need the stain lifted if possible, not paint stripped. Anyone have ideas?