The answer to the most asked question is yes the Mito Meter detects the sub 5G signals.
5G mmWave signals require the low sub frequency signals to create workable umbrella coverage solutions. So as long as you stay clear of strong sub 5G signals, which the Mito Meter detects, you won't have a 5G mmWave issue.
5G Sub frequencies are below 6GHz/6000MHz, the Mito Meter detects up to 8GHz/8000MHz.
(Pictured above is a Nokia-Starhub 5G trial, which like any standalone, or non-standalone 5G solution, it is rendered totally useless without the sub frequency signals.)