It could be, but I doubt it.

The planet was dotted with lights though, which indicates that it's inhabited. It looked as if there was a city on its surface.

The Forerunner home world, technically...is Earth. The forerunners no longer exist, and only their distant cousins, the humans, still survive. That is why Earth is technically the last forerunner home world. I remember guilty spark calling the Master Chief "You are a triumph of your makers...you ARE forerunner..." etc...right before he blasts him with his red ray.

I've heard that the surviving Spartans are here.