I do not know more than is said in this press release, but I assume that they have coordinated to use identical charger specs, otherwise both would lose. It is said that there already are hundreds of such fast chargers installed, so at this point it would not make sense to try to install other incompatible chargers or to make cars incompatible with the existing fast chargers.

I assume that the chargers are more or less compatible with the older chargers, but they must be able to negotiate a higher charging voltage and higher maximum charging currents.

When either the vehicle or the charger does not support the higher voltages and currents, they should fall back to an older and slower charging mode.