Given your tight couple of months and the shoes coming up, I’d go hybrid: set aside enough for the shoes and keep a small $200 buffer then throw the rest at the card. That slashes most of the interest while lowering the chance you’ll swipe again and once insurance clears, set an automatic $25–$50 per week to rebuild the emergency fund and finish the card if anything remains.
If I actually had to boil it down for that model feet on wet sidewalks go for a true extra that model box and a rubber outsole with grooves that move water. Keep the shoe light so he does not tire out and avoid overly squishy foam underfoot. Try them on late afternoon and walk a few steps on a damp area while holding a rail, you will know right away if the grip feels secure. Replace them when the tread looks shiny or flat since that is when slips start happening.