Have him take a hard look at the steering head bearings, their easy to take out and inspect, you may just need new bearings, use a light and look at the races, if there's any kind of a indentation replace them, might be a good idea to just replace them and be done with it.
diddo on bearing i just put new bearings and grease in my steering thingy majigy bearing seat and so smooth really juts buy a new wheel comes true and install a nice quality tire smooth is best for higher speeds and less vibration they arent that expensive you dont need high quality for front tire just make sure it has good bearings in it
oh andit only cost like six bucks witch i thought was pricey for a a set of bearings but everything cost more in ak
Bike shops randomly stuck reflectors into the wheel spokes of hundreds of thousands of bicycles for decades, and nobody ever said that the reflectors caused any imbalance problems by being there.
More than a few somebodies did including me. The three bicycle shops I worked in required you to put the wheel reflectors opposite the valve stem and quite a few customers whom I would guess had bought there bicycles from one of those other shops who randomly placed the wheel reflectors anywhere they felt like also complained about discomfort at high speed until the wheel reflectors were moved or discarded. These were usually people with the lightweight bicycles who rode many miles. Some including myself refuse to use wheel reflectors. The problem is only noticeable at high speed.