The Ask the Audience lifeline was removed from the show, but the reason is straightforward: they had to get rid of the audience due to COVID concerns. According to the Millionaire wiki, this change happened in all versions of the show.
The Russian version (Кто хочет стать миллионером?) had the Ask the Audience lifeline from February 19, 2001 to March 21, 2020. This is pretty easy to verify because the icon is the same: three silhouettes. I found a video showing that icon in three episodes: 2003, 2013, and 2017. Other videos show it in episodes from 2001, 2005, 2018 and January 2020. The same icon is present in the September 26, 2020 episode, but it’s greyed out because there’s no audience.
I also found out that the Philippines version removed Ask the Audience in 2010 (see 2013 video), though the reason for this isn’t clear.
But there are examples where the audience appears to sabotage the contestant. For example, a contestant on the French version used Ask the Audience:
Qu’est-ce qui gravite autour de la Terre ? (What revolves around the earth?)
A: La Lune (The moon)
B: Le Soleil (The sun)
C: Mars
D: Vénus (Venus)
56% chose B, 42% chose A, and 2% chose C. The correct answer is A
After the contestant chose his answer (the wrong one selected by the majority of the audience) and before the correct one was announced, you can hear some people laughing.
This example is cited in the book Sway: The Irresistible Pull of Irrational Behavior (section quoted in full here), which makes a number of claims about how much the audience can be trusted. It looks to be the source of the claim that Russian audiences are often untrustworthy, though they don’t explain how they determined this. They also say that the US audience gets the answer right 90% of the time.
I also found an answer on Quora from someone who said they were on the show and voted on the wrong answer on purpose, contributing to the 5% who voted for that particular wrong answer. (Interesting even if it doesn’t prove much.)
The audience does sometimes get the answer 100% unanimously wrong, though there are only a few examples of this happening, none from the Russian version. (These may not be examples of purposeful sabotage.)