I think I'd be looking for a diff LFS... there might be a local Reef club or something in your area that might help you out. Also cured live rock will help on the cycle. The key is that it is cured...
That is very unfortunate. I have a LFS very similar to that where I live and don't doubt that if I didn't read about things on this site, that I would probably have a destroyed tank right now..
You say that you bought the trigger for $300? On this site it is only $100 (every specimen that I have recieved from this site was very healthy and much larger than I would ever find at the LFS).
Here is the link just so you can check it out: https://www.saltwaterfish.com/site_11...ot_parent_id=4
Good luck on finding them homes!