As reviewed in this video, the method to force unfed first instar Speyeria larvae to start feeding is by exposing them to 24 hours of heated humidity (near 95 degrees F) in a closed container as provided by a nearby lamp with a 60 watt bulb.  The larvae will move about the violets trying to rediapause.  Eventually, after stirring up the larvae repeatedly for roughly 96 hours, they will start feeding.  Once they do, this treatment no longer necessary as you would switch them to a twin cup setup.  Again, see video for instructions.