They may have a camera and that is all very good but did they just give up on the fault finding when things got a bit much for them,it is very difficult to determine where your leak is from without seeing the pump itself,obviously it is in the fuel pump area,did they try cleaning off the pump and starting with someone watching,if it is as bad as you say it is then I don`t see why the leak isn`t being spotted,did they try a mirror to get under the pump for a look?
cdc
August 2013