you may be able to use a baby medicine syringe if need be. you can get them at any walmart or drug store.
you might try tong feeding him to be sure you see him eat. of course the crickets will kick their back legs off to get away so you might want to let them do that and then grab them by their other legs... or by the body.
he might prefer drinking droplets to standing water, so misting his cage might be a good idea. just enough to wet his head and make him lick and leave droplets to drink up for a few minutes. of course make sure it dries up when he's done...
call every local bait shop... and ask some locals you know that like to fish what shops they like. often bait shops will keep wax worms in the off season for us reptile keepers... i have one local that does.
all good advice by v_f!