Although 4e rectified this oversight, I'm not sure why the Panzerfaust 3 didn't make it into the v1-2.2 weapons manuals (especially the latter, as it entered service in 1987, well before publication). This is definitely a weapon system that would have been fielded in time for the start of the Twilight War.
https://en.wikipedia.org/wiki/Panzerfaust_3
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