Hi Selven,
Marketo forms are not intended by default to manipulate data for more than one lead at a time in the database. And forms can display token values (incl. my.token), but surely not populate tokens.
What you want to do (register more than one person at a time) can be done, but either with some programming or using multiple chained forms. If you choose the second solution it is recommended that the second form is on a non tracking LP to avoid any discrepancy s in the cookie-to-lead relationship.
See this discussion on how to create true non trackable LP's: Non-trackable landing page is still identifying me
-Greg