Try feeding it from the stick frequently.  I've found that multiple, shorter training periods per day are preferrable to a single, long session.  At first, you will need to act like a prey fish.  Be subtle, don't force it and even let the angler pursue a bit if it will. 

Frequently, they may "strike" and fail at first.  Taking food from a feeding stick is different than taking a live fish or shrimp.  They may even swallow part of your feeding stick at first.  But, as they learn they will recognize the food and get much better at taking it from the stick.

When it finally eats don't feed it again for a week or more.  Less is more in this case.

Also, I've had good luck finding ghost shrimp at Petsmart.  I've kept them in a mason jar with an air bubbler for weeks at a time.  I feed the shrimp for several days before I feed them to the fish.  Again, one or two ghost shrimp is plenty for an angler each week.   You will want to ween it off of the FW shrimp sooner than later.  But, job 1 is getting them to eat now.

Good luck.   I'd love to see some pics!