So I'm a little curious as to what you mean when you say your frog is vocalizing. Is he actually making a mating call or just kind of squeaking about things. My male ornate will making noises when being handled, and much more so when he isn't feeling well like the couple times he has been a bit impacted. I am under the impression that these vocalizations are out of pain or discomfort. The true calling only seems to occur when he is in a good mood and feeling well.

For the worms, they don't like the taste of anything other than nightcrawlers, the others give off a flavor they don't like. If it's bad enough they may avoid any worm, they are smarter about their food than you might realize.

If he's actually spitting out the food, take him to a vet.