I’m not sure you can sustain the current pulse or more importantly the pinch/plasmoid for 1000X the time. The PF is by nature a fast pulse (~100 ns) event driven by instabilities in the plasma. To stabilize the pinch would eliminate some of the physics that makes efficient fusion possible. These instabilities are also driven by temperature of the plasma and the speed the plasma travels. By operating at 50 atm, you are likely to quash the conditions needed to generate fast ions. LPP operating at 80 Torr is a huge departure from normal PF operation of 1-20 Torr. I’ve seen mentions of atmospheric fill pressures in the long term but the jury is still out on an upper pressure limit. Plasma physics might not be kind enough to allow such high pressure fill. If I were to bet I would guess the operating reactor will be sub-atmosphere at room temperature. If heated the ambient pressure could be greater than atmospheric pressure.
Scanning the pressure to optimize radiation yield is commonly done by those that operate PF devices. Models and semi-empirical relations provide a bounding range but the pressure scan is essential to find the real answer.