I have not heard of anything like that... I think your best bet would be 2 subscriptions and sharing access between 3 of you.
You can use one subscription as well (but you will have only half the tests/questions and potentially will violate terms and conditions)
You can also do screen share via Skype or something like that during the test session but I don't think that's what you were looking for...
Thanks for the quick reply.
What you said makes sense. Can you recommend me which subscription service shall I use for the same? I know a lot of threads must exist regarding this choice, but I would just like to hear what worked for you, or in your experience.
Yes, screenshare is something i am not looking forward to.