The highly active M dwarf star, YZ CMi, was simultaneously observed by the Transiting Exoplanet Survey Satellite (TESS), the Neil Gehrels Swift Observatory (Swift), and the Very Large Array (VLA) in 2019 January. An extreme flaring event (>24 minutes, ~7.6x1031 erg) occurred on 2019 January 25 that was detected by all three observatories. TESS re-observed YZ CMi in 2021 January, this time at 20-second cadence, which allowed the detection of smaller flares and better resolved flare morphology in white light as compared to the 2-minute data collection mode. We compare flare rates between both TESS observation periods and analyze the spot evolution in TESS Sectors 7 and 34, due to changes in brightness variability activity from the two different TESS sectors. Simultaneous observations were also taken with Swift, the Neutron Interior Composition Explorer (NICER), and the CTIO/SMARTS 0.9-m during Sector 34. We analyze the energy partition of flares and compare the flare frequency distribution (FFDs) of events observed simultaneously by the different observatories.