Technician reported the P3 inlet sensor on an A320 was installed incorrectly and the damage caused required an engine change.

Narrative

DATE #2 engine was being changed due to a P3 inlet sensor which was improperly installed. This sensor was installed to the engine fan case with cherry max rivets that eventually sheared and caused the sensor to bounce around in the fan case causing the mount holes to elongate. Engineering was contacted and they found a permanent repair which was beyond our scope at this facility but verified that solid stainless steel rivets is what mounts the sensor boss to the engine case. The damage caused by this elongation led to the engine change which was done by contractors hired by Company. While the engine installation was occurring I inspected the mounting of the new engines P3 inlet sensor boss and found it to be mounted with cherry max rivets just like the one that was taking off wing. I immediately [contacted] engineering and my boss the Station Manager NAME and informed them of my findings. I stated ' I'm not trying to open Pandora's box but you might want to consider issuing a FCD (Fleet Campaign Directive) to inspect the entire fleet for the sensor boss installation'. Neither NAME or the Engineer replied nor called to discuss the issue.In my conscious I believe there are more nefarious acts of Maintenance taking place at [Company] out station. Under qualified Technicians working items/jobs they should not be doing. I'm not sure if this is the doing of the Station Manager NAME or the company pushing NAME into doing the maintenance the unseasoned crew is being tasked with. Example: An engine blade lube on an Airbus A320; not one of the Technicians assigned to the job had ever done a blade lube before. Not one of them had OJT on the task and the crew was asked to fill out a one time RII authorization form to buy back the job. The flying public is in danger. As I stated I cannot attest to the Maintenance done at other Company base or out stations but at ZZZ there are Systemic problems at this base!!!!! I have been a technician; lead; inspector; hangar and line supervisor with almost XX years of experience. This is not right! Something bad is going to happen in my opinion.