G,day Sunfish..
The YWGT TAF is only valid for conditions within a 5 mile radius of the centre aerodrome runway complex. I would use YWGT and YMAY TAF etc for alternate info and the ARFOR for Mt Beauty.
I've flown direct from YMEN-YMBT many times and certainly picked my days. Although not the most direct, following the Hume Hwy to YWGT then direct to Bright keeps you away from high terrain.
There is also a webcam at the Bogong Moth Hotel that you can google, it points at the Mt Beauty Airport and can give you a look at conditions.
Use all information available, don't take any risks, be safe.
Enjoy the scenic approach.