I personally have not tried it, but as far as I know that's how it works (like E-Gift Cards). After clicking activate, the balance should be visible in your new account. Go ahead and try, then please confirm here if it worked or not.
I did use it once or twice. It's exactly like a gift card indeed, and since the transfer of value happens off-chain (yobit account to yobit account) it costs absolutely nothing.
So you can start with some small values for a test and go with the real money only when you are certain you've got it right (although it's very easy).