Blue Damsel attacking my Maroon Clownfish please help! I think it may kill it?

I made a mistake today. I added a Blue Damsel a month and a half ago as a tester fis in my 29 gallon Bio Cube. I heard that they were agressive but thought it would do no harm as it is small and that this would help keep him alive. My main plan is to keep 1 or 2 clownfish and my baby snowflake eel in there for a few months (I can trade anything back to my fish store if it gets to big in that time). I have an anemone in their but it is not a bublle tip or carpet. I can't remember it's name but it has long tentacles, a pink body, and purple dots at the end of the tentacles, it is stinging and eats dead fish. I heard the maroon MIGHT bond to it is this true? My damsel was fine with the clown who is 1/4 in smaller than the damsel for the first few hours with the lights on. I turned off the lights and the clownfish went looking for a cave. There are 5 possible cave spots including the anemone the eel uses one with a shrimp, and the rest is apparantly owned by my damsel. He went apeshit on the clown when the lights went off, chasing him around the tank. The clown is not as fast and won't fight back. I am worried the stress will kill him what should I do? I can't go back to the store to trade in the damsel for awhile and it is really near impossible to catch him he has tons of hiding spots and his really fast. What should I do?? Wait it out? I tried re arranging one cave so the damsel would be confused but it didn't work. how can I maybe get the clown and anemone to bond? should I put them in a small bucket close together so they notice each other? should I try and trap the blue damsel? I have no other tank... Please help people