How long can I keep a dead cricket in a sling container?

I found some mold on the fake leaf and want to change the substrate and give the container a quick wipe. I plan on using dryer substrate and only misting the side once a week since my sling is an OBT. It's definitely too moist right now.

I killed a cricket and startled him while he was eating. It's been a couple of hours and he hasn't gone back to it yet. Could I keep it in there until tomorrow?

Yes, overnight for sure. Often I see my slings chomping on a cricket leg the day after I offered it to them. I don't think the cricket will become foul for a couple of days.

honestly with my slings sometimes it's IMPOSSIBLE to find the dead cricket. If you notice the cricket without having to taring the cage apart, take it out within 2 days or so. If you don't find them I wouldn't really worry as long as your enclosure doesn't start to smell or get overrun with mold.