The Master Chief holds the communicator in his helmet. Kyouya was not in sight, but he nonetheless continues to transmit the information right over to him -- and receiving the information about the rest of the mines.

So we're taking right and center, he comes to think. With the way the mines had all been laid out the night before on the field, they would all the manageable in the middle of the crisis.

Once it's done, they could board the ship.

"Are you coming?"

Jokingly, but even then, he was still going to protect his position if need be, wherever he was.