I've decided it is prudent for me to only try to raise one of these at a time. I thought about raising this one, too, but the prospect of trying to find enough caterpillars for it to eat was too daunting. I wish the other one would branch out and try other things. I've been trying to tempt it with other insects but so far no luck.

That's odd. They are usually pretty willing to eat just about anything. Sometimes they won't eat as much if they're about ready to molt, especially the 5th instar molt into adulthood.