No. Table 1 shows that nothing was added.
Anyway, you could fill the whole thing to 10 atm, let in air, and it wouldn't burn at 250 W for a day. Do the numbers yourself. Cheat! There are on-line calculators for the ideal gas law. Nothing to it. The question is: why didn't THH do it? It is weird making claims like this without any quantitative analysis.
Not removed. You just close the Swaglok valves. Those things are amazing. When there is no reactant in the vessel, the pressure stays the same for days.
It also an excellent leakproof vessel.
Jed - you really do not read what I write. You are including the (tiny) gaseous D2, not the larger loaded quantity. Unless the whole loading process was done with valve closed? In that case all is good.