Jim certainly doesn't think anything nefarious is going on. He's in uncharted waters, but at least some of the currents are familiar. Spoilers from Ambassador Spock, a time-traveling Romulan who decided to screw everything up for generations to come... Things like this are nothing to treat lightly. If it comes down to having to compare notes with the other Jim, then so be it, but that's a matter for another time, probably.

"I do, actually." Jim may be dressed in civilian clothing, but his communicator is still on him as per regulations, and he pulls it out of his pocket. "I picked up a PINpoint attachment for my communicator a ways back."