It will take a few seconds after a start to register 14V on the cluster...you're fine there.
I also think something is loose or corroded...ground, battery cable, cable under the +terminal under the hood.
But, tell him if the battery light flashes again and increases its frequency until it's on all the time, that he needs to get home right away because he's driving on battery alone.
I'm so depressed. No one wants to come see me in NYC: Sat, Oct. 8, 6 p.m. at Greenwich Village Comedy Club.
Mangofy your E46!