My own comments
1 - If your dealing with Case 2 (CTR TK concern) the leak is presumed to be in the plumbing, not the tank.
2 - You're supposed to land ASAP (nearest suitable airport). If the leak is CASE 2 then leave the fuel in the CTR TK unless it's absolutely neccessary to use it. If it is needed to make the nearest suitable field then the 3000 kg figure assumes a worst case scenario of an almost full CTR TK and allows for full transfer, or as much as possible, from CTR TK without risk of spillover into the surge tank. If there was significantly less than full fuel in the ctr tk and space was available for it in the inner tks then you could indeed select the CTR TK pumps on again but why bother unless you need the fuel. You're just wasting fuel out the leaky plumbing.