It sounds almost like a faulty ignition switch. The contacts inside the switch can wear out from years of use, especially if you have a large bunch of keys hanging off your key ring. A faulty ignition switch will behave just as you described…the vehicle will die suddenly for no apparent reason.
However, in the case of a faulty ignition switch, the driver can usually restart the engine right away and drive on. The fact that you have to wait 10 minutes before the engine will restart is not entirely consistent with a faulty ignition switch. I don’t know anything about Suburban diesels, but it sounds like an intermittent electrical problem in the fuel system…like power to the fuel pump is being interrupted, or the fuel pump itself has an intermittent problem, or the wiring to the injector pump has an intermittent problem, or even an intermittent problem with the computer module.
Unfortunately for you, intermittent electrical problems can be very difficult to trace. You’re going to have to be persistent until some mechanic figures it out.