Thanks to some great help on the SDIY list, I know what the problem was with the EG simulation. There is a transistor with the base wired to the emitter and then wired backwards to a diode which resets the Flip-Flop. SPICE did not like this and did not properly model it. Oren, from the SDIY list was the first to recognize this transistor was acting like a zener diode. I merely replaced the transistor in the simulation with a zener diode and the circuit works perfectly. The zener voltage determines the peak voltage for the envelope, for a transistor that will be about 5 volts.
Here is a screen shot of the EG. The red trace is the "key down" and the green is the output. The first trace shows that in normal operation, even a short duration key down causes the EG to peak then decay. Next, I held the key down past the peak to show the EG will peak, then decay to the duration level, then decay to 0 with key up. Next is a trace with the Damp switch on. The EG decays immediately and quickly to 0 after a key up. Last is the Quathin switch on. It, too decays immediately on key up, but decays with the decay setting rather than quickly as with the Damp.