There are a couple of FF tricks here that change the numbers. First, the brehmstrahlung is minimized by tweaking the ion/electron energy levels so they fall in a “gap” where ions can’t accelerate the electrons and generate X-rays. Second, temperature is measured in electron volts, and tiny-ness is FF’s friend; it’s not like raising the temp of a containment chamber; the relevant energy levels are attained within a microscopic plasmoid, which self-contains with EM fields.
As of the date of this writing, results for generating the temps and compressions needed are coming in even better than theory predicted.
