The few actions outlined here will alleviate the noise generated by the rear of an electric Yamaha Golf Cart.
Reach beneath the rear of the cart and spin both axle tubes.
Tighten the nut that secures the bub.
These should eliminate the background noise you were hearing.
The critical point to remember here is that the electric Yamaha golf cart does not come equipped with grease points, and searching for them is pointless.
Check the nuts on the axle hub if you hear a noise in a 2012 G29 Yamaha golf cart. You should pay particular attention to the steel collar between the seat and the bearing. The collar may be moving and generating noise.