He owns the approval for return to service no different than if he did all the work himself.What are the consequences for the A&P in a situation like this?
10 to 1 he looked at it but not as closely as he should have since he probably had a high level of trust in the people working the install to include the pilot.Hundred bucks says the A&P never looked at it before signing off.
Yes. Technically per 43.9(a)(3) each person who performs maintenance on the aircraft must list their name in the entry. So this is actually an example of a proper logbook entry as shown below.Did they really say 5 different people had signatures in the logbook regarding the install?

https://data.ntsb.gov/Docket/Docume...e=Excerpt from Mx Logs FA261_Redacted-Rel.pdf