only a couple ideas come to mind, he has unshed skin stuck on his toes which is irritating him. Or the bites are irritating. I suggest a soak in luke warm water deep enough to cover his feet at least but a bit deeper to armpits wouldn't hurt. Check for mites as well as these can cause irritation though I would not expect the toes being the likely area for mites to be.

A betadine soak will help with any infection in the bites, but topical antibiotic ointment will help too. Also, move him to a simple and easy to clean substrate like papertowels. Make sure uneaten crickets are removed from the cage after each meal.

Over grown toe nails could be causing issues too.
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PHLdyPayne

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