Thanks for the image... Time for me to go drink a nice glass of vinegar. Abusive comment hidden. (Show it anyway.)
If I remember the timing of things, by the late 90s there was already evidence that the Higgs boson would be heavier than ~90 GeV/c^2, and some expectation, that if it existed, it would be below 1000, and possibly in the 100-200 range.
It looks like some writer just too the Planck mass (the stuff under the square root), a "natural" unit of mass, and multiplied it by other constants until getting something within an order of magnitude of what was known at the time. It would have been closer if they dropped the pi, and just stuck with the fine structure constant (which is almost 1/137).