Cas senses something as off, but feels as if it's safe to assume that while Dean might have some post traumatic stress from being locked up for so long, it won't be near what he suffered after hell and after purgatory. He hopes.

"Tessa is here," he nods to the reaper standing not far away but keeping a respectable distance though it's obvious from her posture she wants nothing more than to run over and start mother henning all over Dean. "I convinced the other reapers that their presence here was unnecessary." He doubted that Dean would enjoy waking up to a crowd looking for instructions.