We've had some heated discussions here about whether peanut butter is a temporary or permanent fix.
NXT is a real bad stainer. Here's my suggestion, you need to use a solvent or strong detergent to dissolve it. If the surface is textured, you will need to agitate it with something to get into the texture, the tricky part is agitating it, with a brush or scrubber, without damaging the texture of the plastic or surrounding paint.
I'd try some IPA or your best APC.