He mostly wouldn't have been found out if the quality of his posts were the same when he posted in the Indonesian local boards, but it seemed like some people noticed the changes in quality of his posts when he switched over to the Russian board, which led to people having suspicions that the said account has been hacked/sold/owned by someone else.
So you really think someone has been able to notice a change in the quality of his posts between his russian posts and his indonesian ones? 
Well I know russian people are very clever but I don't think many of them are fluent in Indonesian...
What is not tolerated IMO it's rather to switch from only one language writing to another one without writing anymore in the previous one...
Trying to learn another language is just a BS justification in this case to try to fool people IMO.
The account was active from 2014 to April 2017 with Indonesian and English language.
Since November 15, 2017, this account was found in a person who writes only in Russian language.
Since November 15, 2017, this account was found in a person who writes only in Russian language.