Possible for a cleaner shrimp to kill fish?

I have been keeping saltwater tanks for years. I just had a really unusual situation happen because I typically don't keep inverts in my tanks except snails and a few scarlet hermits. The tank in question is my smallest a 29g biocube HQI. This tank has been up and running for over 4 months. I've had 4 fish in the tank for several months now. A B&W ocellaris clown, orchid dottyback, helfrichs fire fish and a yellow assessor. All four have gotten along without any aggression for months and school together. My tank params are 0 ammonia 0 nitrites 0 nitrates( almost zero) temp stable at 78. Alk 9, mag 1250, cal 450. Ph is stable at 8.1 and I keep my SG at 1.024as I do with every reef tank I have kept.This tank has been thriving along with the fish for months. My dottyback went missing several days ago and this morning I found what was left of my helfrichs being consumed by my cleanup crew. The only thing that has been added of changed in months was the addition of a skunk cleaner shrimp. This tank is very stable and the only thing that I can think of is that the cleaner attacked and killed the 2 fish that aren't as mobile at night as the other 2 are. Any thoughts or advice would be welcomed.

Thanks for the reply Adam. I can see 1 fish dying for unknown reasons. But 2 healthy, eating fish dead in the time since I added the cleaner just seems too odd. Has anyone had a skunk cleaner kill docile fish? The shrimp is small/medium sized. The 2 fish are the only 2 cave dwellers that don't swim around at night like the clown and assessor do.

Tank was constructed with BRS dry rock as are all of the tanks I build. Every coral that goes in gets a bayers/coral RX dip and sometimes peroxide to prevent anything from hitch hiking. I've viewed the tank at night countless times with my red lens mini light. Just odd...

It's not unusual for fish to die in groups. Illness can be contagious. Certainly not saying that proper care was neglected because flat tires are the same way. A month ago I had a flat fixed as they removed a visible nail. Last week the same tire picked up a grabber screw and I'm not even in construction. Luckily both punctures were in the fixable area of the tire. I'm keeping my fingers crossed for my tire and your tank.