Fan2eng

Has anyone successfully flat towed a 2024 Silverado ZR2?
I followed the Owners Manual instructions to put the truck into flat tow/dingy tow mode (including putting the transfer case into Neutral and disconnecting and securing the NEG battery sensor stud and cable). During slow roll testing the electronic Parking brake engages soon after it starts to roll. I was under the impression that removing the NEG battery cable from the battery sensor connection would prevent the Parking brake from engaging automatically. After 3 tries following the 2024 Owners Manual directions verbatim with the same results I'm stumped. I'm wondering if the instructions for disconnecting the battery outlined in the manual is correct? (I found out the Owners Manual sequence for putting the transfer case into Neutral was incorrect when flat towing my 2012 Avalanche...). Any constructive response is appreciated. TIA