You wouldn't be referring to the agreement of rouble transfer that Vähi signed before Laar's PMship?  The one that the State Comptroller's Office condemned as irresponsible and unlawful?  Nope  illegal agreements can't be considered as sufficient basis for giveaway of billions of roubles.  It might have made a heck of a bribe to the then-reigning Soviet authorities, sure.
As for the SUR->EEK exchange, nobody was forced to exchange their cash.  I retained a few of my hard-earned rouble banknotes as memorabilia myself.  (There's no need to remind you that they lost all financial value in a few short years.)  It just so happened that BoE's rate was among the best available rates, and while SUR kept falling, EEK managed to brake the inflation down to a manageable level.
Remember: events from this era are generally poorly understood by the general public.  A lot of rumours circulated, some better, some worse.  Some of these rumours were politically motivated.  It was an era so hectic there was even no Internet!  Taking a random thing you read or hear about anything from the early 1990s Estonia is likely to mislead you. Εμπρος!