Are the 5 monitors to be viewed in real time during the meeting? If so, Vegas isn't involved at all. Vegas is the wrong thing to be thinking about when handling live feeds.

If you are making a recording of the meeting with 5 cameras which are then to be combined into a single video then you don't need to output to 5 monitors at all. Capture each camera one at a time after the meeting is over and use any of the multicam editing techniques often discussed in this forum.

Do you need to accomplish both at the same time? You'll still need some sort of live video system to run the individual monitors. And the video will still be captured from each camera one at a time after the meeting is over.

Do you need to have the recording play back 5 separate video streams on 5 separate monitors simultaneously? If that's the case then you will produce 5 separate videos and you will need some sort of playback equipment that can sync them together. You can edit and produce the individual videos in Vegas. After that you need some hardware solution to facilitate playback.

Your question reminds me of the "three legged dog" questions my physics teacher used to put on his tests. He'd ask something like, "if a dog runs off a 300 meter cliff at 5.5 meters per second, how far from the base of the cliff will he land if he only has three legs." A large part of solving the problem included realizing that the number of legs didn't matter in the slightest. Some students would work very hard at trying to work 3/4 into the formula somewhere and would get the wrong answer. I bring this up because i'm wondering if the same thing might apply to your original question when you say "There have been 5 persons at the meeting...". I don't know what that has to do with the rest of the problem. Unless you can explain it in more detail, i suspect that you're letting this statement make you think the problem is more complex than it really is.