Any amp that has not been used in a number of years is likely to have developed a number of problems, but depending on how it was stored, I doubt that it would require the replacement of the board. Has he checked the tubes?
If the amp is dead silent, check the speaker, the wiring and the plug/jack for corrosion etc. Oxidized connections at all of the jacks would be the first thing I'd look at. Then check the tube socket connections.
Hope this helps.