Yes, Christine's photos are too good to leave hidden in another section of CNM hence the M. convecta suggestion, even though armyworm larvae are difficult to separate, to get the pics into 'Moths'.
Thanks Owen. And sorry Don, my attempt at rearing a case moth seems to have failed, after months of eating, it has been hanging in its case (larger case than when I captured it) for around seven weeks now, so I guess it is not going to emerge. In general I do not touch anything, I just photograph if possible, and leave them to get on with their lives. Almost zero chance of refinding the caterpillar anyway.