I have painted many a truck in a 30x40 area with a good exhaust fan in the wall. We have a 65K LP infra red heater hanging from the ceiling and use it all the time to dry paint after the fumes have cleared. Been doing it since 1984. Also have a smaller one mounted on a 100# tank on a 2 wheel dolly, use it for spot heating and paint drying.

Some spray booths use gas infer red heat to cure the clear after the fumes are cleared out.

So to answer your question, no it won't hurt the paint.
But you got to be careful in smaller inclosed areas with portable gas heat.I don't think I'd try any kind of heater with a blower around paint. Keep any open flame well up off the floor in any garage.