Jason wasn't sure why he was there, but he couldn't leave just yet. He was supposed to enter the subspace along with everyone else—the first group had already left, while he, along with many others, were still detained in the temporary camps.
He thought the mission was urgently critical, but there could be various complications he wasn't aware of.
He was fine with commiserating with others in the camp until his elder sister called and brought him to a different tent, not giving any reason as to why.
The only answer she had given was: "You'll know soon."
She left after saying that, and that was at least two hours ago. He even thought his sister was keeping him from entering the dangerous subspace infested with forsaken. But that wasn't Jessica's style. She would rather beat him to unconsciousness if she didn't want him to enter the subspace.