yellowheaded jawfish died

So as my earlier post...I got a yellow headed jawfish from LA...I had it a total of 3 weeks. I put it into a 10 gallon quarantine tank. Which from what I have read my have been the issue. The fish NEVER seemed to be settled. It would burrow in one place for a while and then move around the next day. Around week 2 there was a day or two where it ate food that passed by and was looking like "Hey this guy is doing good"...about 2 days after that...maybe the next day I introduced a tanakas pygmy wrasse. I had read from ALL the websites that this was actually a really good fish to go along with the jaw and would not cause any issues....so with the lights of and everything I acclimated the tanaka. The tanaka did fine...but the jawfish seemed to act weird. It was laying not out in the open but close to the rocks....and breathing heavily. I couldnt figure out what was going on. I observed the tanaka closely and found no signs of him abusing the jaw. Again...tanakas are EXTREMELY passive and alid back, if anything the JAW should have picked on him...yes people do the research...I'm right. Not a lot of people on here own tanakas...trust me. Anyways...I also had about 3-4" AT least of coarse substrate for the jaw...and a BIG piece of half moon shaped PVC pipe, I also had about 3 good sizes of LR...one was perfect with a flat bottom for him to make a home. Water parameters were perfect! I wont say what they are...there just perfect okay. So my friends, why after 3 2 weeks did it eat...then after the wrasse was introduced not eat and breathe heavily then die? Was it all because of the wrasse? Was it because it didnt come in that healthy from LA? I think its a combination of the tank being small...it not coming in healthy from LA...and introducing the wrasse was just too much at once...along with me adding some sand in the tank after about 2 weeks. But a top leading expert says clearly in his article...if a jawfish continues to move sand replace it...which is what I did. Look folks I'v been in the military for 10 years. I know how to follow orders, and do things dress right dress...if the fish died its not because I didnt follow protocol...so please give me some insight. My water was at 79...no emerald crabs or any of that mess either.