Russian anti-air weapons
Check about old PZRK "Igla" - Max altitude is about 3000 meter.
That VK public account is ruled by activist, and he put there any thing, that he found on youtube or on forums.
If someone see a burning aircraft over civil war zone, that think about "successful anti-aircraft operation". But for real responsibility wee need proofs.
Dnepropetrovsk flight control crew is kidnapped, foreign experts are not more on place of impact. That is all about that - case is resolved.