I am just a layperson, but I would ask him to see a cardiologist so all this stuff could be discussed. Perhaps it is nothing, but why not set both your minds at rest.
The doctor told him to keep the report with him at all times in the event something happened to him, but did not recommend any follow up (I thought this was odd).
Not sure if this is relevant or not but prior to this EKG, my son was in his vehicle when it was struck by lightening. He was blinded for a short period of time from the flash and understandably shaken, but did not seek any medical attention (his car's electrical system was completely fried)
A month after the EKG, he exercised in the morning then went to work and felt a sudden feeling like his chest was "caving in". He is not the type to go to a doctor and went to the ER (so he must have been scared). They checked his vitals and told him they were really busy and could he come back tomorrow (they did not do an EKG). He left and did not go back. The problem went away and he has no idea what could have caused it.
I can't really do justice to the question without seeing the EKG. If the doctor that saw the EKG recommended that he see a cardiologist, that is what you should do.