08 club car precedent won’t move

[SilverRXV]

My buddy has a 2008 club car precident. A few months back it stopped moving while he was driving. He replaced the Mcor pedal sensor, the solenoid, and the controller (which ended up being the problem) It was running fine until the other day, but then it came to a dead stop while driving. He knew the batteries were old and going bad so we took his 4 12 volt batteries out, and put my 6 8 volt Trojan batteries that are in great shape (1 year old) in the cart. Even with the new batteries the cart won’t move. Also when charging my batteries in his cart the batteries smell like rotten eggs which didn’t happen when they were in my cart, and the batteries were fully charged when we put them in so I DK why they are gassing. Does any of this ring a bell for any of you? Do we have any idea what’s wrong with the cart?