According to many posters the motors connected to the dead ports still have red status lights but do not communicate with the brain, which suggests that they still have power while RS-485 is dead. I would expect power line connected to eFuse to have more capacitance (filter caps) and much better chance to survive ESD than the low-capacitance data lines.
I dug deeper into RS-485 driver SN65HVD1782 datasheet and it states that when in active HI state the damage may occur with as little as 30V voltage on the inputs and, also, page 21 recommends installing SMBJ43CA TVS diodes to protect input lines, which I don’t see on V5’s pcb.
Bi-directional SMBJ43CA and SMBJ43CD devices could be bought for as little as $0.11 in large quantities or for $0.44 for non-volume orders. This would be similar to the cost of SM712 ($0.87) to protect 2 channels on one RS-485 port.
There is one local team that has already blown 10 ports on their V5. All with cap flipper motor (on the end of DR4B) connected with a long pre-made cable. Apparently their robot and/or their practice field has something special that makes ESD strikes worse.
I bought several SM712 earlier today and will try to make a line inserts to see if they could be effective to protect their ports before they RMA their V5 brain.