I'd be nervous about inserting a tape someone else used in a different camera if I were in your shoes, you never know what their tape deck looked like, a lot of people don't baby their VX's the way they really should, so I'd be scared of importing dust / dirt / lubricant leftovers from the heads of the first camera onto mine (heads are really easy to get dirty, changing tapes out in the open and whatnot), I've seen all kinds of glitches result from sketchy tape switch ups, even heads getting misaligned for good once (I guess the former camera had brutalized the tape). Technically you should be somewhat safe but practically it should be a last resort type of situation. I know I like to use fresh tapes only because I've had, and seen, many cameras suddenly go to shit exactly due to that tempting 'meh, that'll do' mentality when it comes to tapes, VX's and others.
Think of it as fucking a stranger without a condom. You can always do it, but...