Good you saw him eat something!

I'm no expert on frogs, since I only keep toads, but one of my Bufos used to do the pacing and they do it everytime their tank substrate is changed (every three-four weeks). To me it indicates stress.

I gave my guys a larger enclosure, since they'd grown, and plantes two large ferns, got two low ceramic caves, soft rocks, succulent plants and generally do alot to maintain an enclosure that's as natural as possible, with numerous amounts of choices for hiding/burrowing.

I'd check how he's interacting with the other two frogs, especially if they are bigger than him: Are they food agressive? Is he stressed out by them? If they are bigger than him, that in itself can be intimidating, since most frogs and toads eat offspring of their own species. And if they are food agressive - and there's two of them, he might be too stressed to go to the bowl, if they're there first.

Otherwise I'd leave him alone for now, to give him a chance to cool down. Check if your terrarium is placed in a highly trafficed area where he might feel too exposed.

I don't suspect a troll b'cause the crickets are dissappearing, but he's loosing weight. Before I was introduced to the feeder bowl method for crickets, I thought my two Bufos ate ALOT of crickets. Until I found a literal night club under their water bowl 8.l and in their plant.