Dont get any inverts untill you get the shrimp out. They should become snacks.
Try luring it out with "the water bottle trick." You get the bottle, cut off the top, flip it and stick it in the opening, creating a funnel. Place a raw cocktail shrimp (one we would eat) in it and wait. Don't place the bottle in the open; place it near the back so he will be lured into it. The shrimp wont be able to get out of the funnel since the opening is confusing for them.