“Teleporting quantum information is now a practical reality,” asserts Deutsche Telekom. The firm’s T‑Labs used commercially available Qunnect hardware to demo quantum teleportation over 30km of live, commercial Berlin fiber, running alongside classical internet traffic. In an email to Tom’s Hardware, Deutsche Telekom’s PR folks said that Cisco also ran the same hardware and demo process to connect data centers in NYC.
AFAIU you can’t determine whether the state on the other side has been collapsed. All you can say with certainty is the state on the other side after you have collapsed yours.