actually no need to speculate about this. every user only have one time chance to use the promo code. after claimed the code, they can play for the free spins, if they win, they need to complete x100 wager requirements and one deposit. and then to complete the requirement, they have 30 days before it's expired. if not claimed till the end of period, user loses that bonus and the winning amounts.
I think with this is explanation you made here, no user should have problem on how the promo code is been used, I wanted to say something, there will be no need since you've made clarification to that.
I'm not that kind of gambler that have interest in promo code and all that, I have my reasons, I prefer to deposit to play my bet because I see these things as stress which I wouldn't want to be involved in, good a thing everything about the Promo code is spelt out by Vega Bet, and it is left for user to keep to instructions, so that they won't lose everything, if they eventually get lucky to win with the promocode after meeting up with the requirements.