Mechanic put wrong spark plugs in

So I drive a 2002 VW Golf with 123,000miles on it. I’ve been in and out of the car shop with my car all summer. However this last time I brought it in, they informed me that back in June they put the wrong spark plugs into my car. Since June I have replaced the catalytic Converter, both upstream and downstream oxygen Sensors, and ignition coils. I’m wondering if these things were most likely caused by the mechanic putting the wrong spark plugs in back in June.

Certainly, the ignition coils could be damaged by having the wrong spark plugs.

The O2 sensors wouldn’t be damaged, but they may have been replaced due to misdiagnosis of the ignition problem.

The converters could have been damaged by misfires that may have resulted from having the wrong plugs in.

Yes, they absolutely could have caused the problems. In addition to their physical and electrical characteristics, spark plugs have “heat ranges”, which is the amount of heat retained by the plug. An incorrect heat range can cause the damages of which you speak.

I’ve attached a link to specific information. You may want to read all 5 pages.

To venture a better guess we’d need to know the actual part number of the plug used. Part numbers are encoded, and with that we could determine exactly what was different about the plug.