Ali, it's time to be brave. Your allegations should (must) be reported! This falls into the classification of a practice likely to endanger an aircraft or its occupants. Therefore, you MUST raise an MOR - it is MANDATORY. Theoretically, you have no choice.
Back in the real world, a CHIRP should be the choice if you are squiffy. Or, as Spanners suggests, a chat with the local office.
I have trouble understanding why an engineer would seek to jeopardise the safety of an aircraft, and his career, for the sake of commercial pressure.
It is time to act.