What are calci worms? They're probably something I've heard of called a different name...

Will he hunt crickets if they walk past him? Sometimes that works. You can tear off the crickets' back legs so they can't hop, and make them crawl past him. If you do that though, make sure there's no moss around (looks like there's some moss in your profile pic).
Can you get dubia roaches? Usually you have to order them online, but they're healthy and some frogs really like them.

Also, have you tried rubbing the nightcrawlers and all against the frog's lips? Sometimes if you can annoy them into biting it once they'll realize it's food and take it normally the next time.