N14 mystery miss

I have a 99 N14 Celect plus that has a miss. In January this year i had a miss and ended up replacing heads, injectors pass through connectors, injectors, and complete engine wiring harness. After all that the miss was gone. Fast forward to the beginning of September I had an injector lock up and bust a push rod and destroy the #5 injector. My mechanic fix everything and now I have a miss. he put it on the computer and said #5 was bad so we replaced it again still missing. I tried replacing the pass through no luck. He took the rocker box apart again to scope the cam and followers said they look fine. He told me he is out of ideas that it could be. Can someone please help me. Thank you

 

That’s what I was afraid of. I appreciate the reply.