Forgetting a small detail, that such kind of transactions cannot happen against of the will of a 39% shareholder partner which deserved to receive back in payment as much as the Finland’s pension fund.
Even if the Finland’s pension fund might accept to left unclaimed its debt - a decision no any bureaucrat can take unless being sued and condemned to pay the public loss by their own pockets. This implies a judge or a some kind of court decision but the court/judge should have a good/valid reason to take such a decision even if s/he is keen to bend the law for anti-russian politics.
Because in zeroing the Finland debt, the picture does not improve but for RosTelecom, only. Unfortunately, there is no way to close any deal about the debts positions. Politics cannot be the solution for the problems they created.
Without the agreement of creditors in front of a ruling court, the management cannot sell itself the company assets that they manage especially leaving behind debts or at a tiny fraction of their value. It would be considered more than unfair and it would be challenged in court and the court will assign the propriety and the control of the newco to the previous shareholders possibly freezing it in the meantime.
They can buy the assets that they can reasonable demonstrate that they (morally) own and pay nuts for those are worth near nothing. Like this forum, for example. They (morally) own means convincing the opposing shareholders that they cannot claim about that results (a different business division or branch). Usually pointing out to them that such a business could never being created because their participation in the company. Equivalent to say: you cannot buy our part because our clients will not accept you as their provider nor business partner.
Finally the agreement can be legally viable when Finland can have a profitable company running its business in exchange of some kind of financial loss and Russia counterpart nothing to lose in letting them do. However, we will know more when the Jolla Oy company will be closed down because at the moment it still open but a badco.
The trick of splitting a company in a badco and goodco (or newco) is quite old and in court, it is just an accountable trick to not freeze a profitable business for too long bringing it to close down.
Therefore, in the Spiderman vs Spiderman scenario, the judge is missing… 
Fell free to add the judge by yourself, here above a suggestion! 