I watched this wasp moving the caterpillar, taking occasional breaks, maybe to find a place to dig its nest. (Bug Eric says cutworm wasps paralyze their prey and then dig a burrow to bury it in.) When I came back an hour or so later, the caterpillar was still there but the wasp wasn't. It looks like the caterpillar will now feed ants instead of wasp larvae.
View on iNaturalist
Observed on 2 May 2018.