Never have flown anything with 4 engines, so I don't know if there are different Vmc numbers for failure of the outboard verses inboard engine or both.
Failure of outboard engines require lots of rudder and power reduction on the corresponding good engine to maintain flight. If you lose an outside engine, you essentially are looking at flying on two engines. If yo lose two on one side, you are in a world of hurt if it happens right after take off and you have a lot of fuel. I used to fly EP-3Es. We had the same engines as the C-130s. We would constantly practice one and two engine out flight. Never had an engine failure on take off, however a good friend of mine did. Full bag of fuel and a full crew made for a very interesting return to the field.