Wiedenhopf
In a word NO using cabin air pressure does not mean pressurising the whole fuel system to cabin pressure. Quite clearly the system would apply a regulated pressure to the fuel and stop the flow when the fuel tank is empty.
The vent/ surge system does vent the whole fuel system and maintain the whole fuel system above ambient pressure to help gravity feeding of fuel should the boost pumps fail, so in the very worst situation of unregulated cabin pressure getting into the centre tank this air would be vented overboard via the vent/ surge system.