Most residential power is dirty to some extent, and AC/DC converters are supposed to be able to cope with a wide range of input distortions. For the problem to have worked its way through all of the safety components in both the laptops power brick and its internal electronics means that the distortions must have been particularly high amplitude, and at frequencies that couldn't be easily filtered out (very high, very low, or both).

Electricians that aren't particularly well trained, or particularly experienced are probably not going to be able to diagnose this kind of problem.

This is really a problem for an electrical engineer.

Unfortunately, in most jurisdictions, engineers aren't allowed to perform these kinds of repairs because they don't necessarily have the certifications to perform work on live wires.

Most electricians can only trace wires and identify visible faults, and replace things that aren't up to building codes.