Maybe I'm missing something basic, but why is this a remote issue? The person who interviewed is not the person who tried to start working, and the company immediately saw this. In the old days one could also try to fraudulently arrange to have the person who did in-person interviews be different than the person who shows up on day 1 ... and you'd likely still be caught, right? Is the only additional risk of remote work that fraudulent applicants have a broader pool of fake interviewees to hire?
Generally in my experiences as a candidate, _someone_ on the interview loop is with the team one would end up working with, and should catch this kind of thing. Generally as an interviewer, whether remote or onsite, it hasn't been part of the process to check the ID of the person I'm speaking to (and I'm not confident I could spot a fake anyway). Thinking back to a time where I did a day of interviews at a BigCorp and I don't know that any of my interviewers were on the specific team I'd work with ... I don't recall any rigorous attempt to establish my identity on the day.
Generally in my experiences as a candidate, _someone_ on the interview loop is with the team one would end up working with, and should catch this kind of thing. Generally as an interviewer, whether remote or onsite, it hasn't been part of the process to check the ID of the person I'm speaking to (and I'm not confident I could spot a fake anyway). Thinking back to a time where I did a day of interviews at a BigCorp and I don't know that any of my interviewers were on the specific team I'd work with ... I don't recall any rigorous attempt to establish my identity on the day.