We do not want to add a second translation of the same language. That will be a lot of wasted effort, is confusing to users, and we can only default to one language when we detect the user is Russian.
There are currently 29 contributors for Russian on POEditor, and new contributors can still sign up. There are still occasional contributions being made. As I have stated before in this thread, you are welcome to sign up and make improvements, but to prevent edit wars, you should make sure there is a general consensus in the community before making any significant changes. I cannot be involved in this, because I don't speak Russian at all so I can't make any decisions on which translations are preferable. However there are various ways to agree consensus - for example you could run a poll to agree a change in terminology, and use the results to justify a change, even if some people disagree with it.
I'd add that we have not assigned any official translators, so Scirra is not officially vouching for any one person. If anyone claims that Scirra favours their translations, they are wrong, and you should ignore those claims. No individual or group of individuals has sole control or responsibility for the translation, it is a community project. If necessary you should overrule any such people if there is broad consensus for a change - but you should make sure there is a good process for that so it doesn't descend in to chaos.