Yeah, so if the Unleashed CLI is similar to other OS (vSZ) CLI commands, something like the following might let you adjust the channel width beyond what the unleashed GUI allows.
set cwmode : set cwmode {0|2|3|4|5|6} (0=20Mhz, 2=40MHz 3=10MHz 4=80 5=160 6=80_80MHz)
-- Set 11N channel width mode
so "set cwmode wifi1 <5 or 6>"