For the number of ships, by TOS there are only 12 Constitution class ships, so there might not be more ships to send. We're a year or so out from the Klingon war, and it doesn't seem like the Federation is in a position to quickly replace ships. They already lost the Cayuga. Also the admiralty obviously isn't interested in a Gorn war at all, and certainly not over this planet or the potential survivors.

I will say it's been shown that Pike is just not a fighting captain. He's not the person you want in a combat situation. It does make me wonder why he's a Captain but idk. They really should send the Enterprise back on a deep space mission of exploration and have someone (who is not an evil mirror universe person) more like Lorca or Kirk running these border conflicts or something.