The bad connector would only cause heat at the connection point due to the increased resistance. It wouldn't affect the ESC at all. There must be something else going on if the ESC is getting too hot. Have you checked your driveline for any binding?
Thanks for the replies guys. No binding at the driveline. I think I just got a bunk ESC. I ordered a "brand new" one last night to swap out and see what the difference is. I am also going to be going with Deans plugs as well. They look much easier to solder to me from the vids I seen.