but still , they used to have some followers

This is not a Russian exchange, Russians wouldn't do such a primitive scam. This guy's name is Milan Sharma, skype ID :78996918be236ef8 , he is a British of Indian descent, living in UK.
You can check the screenshot in telegram, it is an official Terra Coin channel https://t.me/terracreditupdates/361. We did some work for them, implemented on coingecko, but haven't checked it before, so if you type "boostexchange" - it will show some scam reports. They haven't payed us. You probably thought that these were Russians cause Russians spotted first, that boostexchange is a scam and posted some info in Russian language.