Now that I think about it, that solder job may not be all that bad. Remember, those are SMT (surface mount technology) components and are placed on the board by a pick and place machine and wave soldered. That's why they are mounted on daughter boards. The main board is hand soldered using 'through-hole' techniques. The big blob of solder you pictured might be purposely put there after the fact, in order to use the 4 channels of the FET in parallel. I have seen this done before. Be interesting to see if further boards have this.
Or it's just a crappy solder job and it blew your electronics