I'd forget the meat. Mine have never had it as even a "treat" (my dog gets "treats" for sitting and fetching, i personally think axies need nutrition, not treats)
I still chuckle at the mental image of a wild axie bringing down a cow and tearing it's heart out....
Anyways, i'm not trying to get into that argument
.... worms or pellets, as above.
Different stressors can effect their appetite - tank parameters, temp & cycle
Is you tank cycled? Is it getting too much light, too much noise or passing traffic - you probably already have, but check out the requirement page and check the list, make sure you aren't doing something to stress him a little -
Axolotls - Requirements & Water Conditions in Captivity
Other than that, persist with the food.
Just last week one of my guys went off his food.
normally, i only have to walk past or up to the tank and the greedy buggers are poking out of the hides for food, i've always fed by hand, and they follow my "magic food hand" everywhere. For no apparent reason one of them just refused anything last week, avoided me like the plague, wanted nothing to do with the magic food hand.
I tried all sorts of different ways to try to feed him (without stressing him, i tried a few times then just left him, the fat bugger would take weeks to starve!
)
After about 7 days and only 1 small worm and a pellet or two eaten, he did a nice big poop. A sudden interest in the magic hand the next day! One big worm and 3 pellets next feed, and he came straight out for it!
So, try some different things, make sure the set up is not stressing him, the cycle is working or done, but persist with it without stressing him if uou can
Bren