Surface to air missiles use various forms of shrapnel depending on the missile, this is basically 100% a SAM. This also looks very similar to the damage from the other airliner Russia shot down a few years ago with one of their mobile Sam units.
FlAK stands for FlugAbwehrKanone, meaning air defence cannon. What you mean is shrapnel, which air defence missiles use to shoot down planes.
The Gepard is a SHORAD system using airburst autocannons to hit stuff, but airliners usually fly too high for that. The Russian equivalents from newest to older systems are the Pantsir, the Tunguska and the Shilka, IDK if they still use Shilkas though.
plane was hit at about 3km, so within range of even MANPADS and pantsir guns, but it was a bit misty so IR and photocontrast guidance is out. azeris suspect command guided pantsir missile, that is 57e6 or similar, which has some 7x less explosive than buk missile used in mh17 shootdown
shilkas are still good against drones so i suspect they do use them. ukrainians use everything down to 12.7mm and 7.62mm machine guns for this purpose
What sort of gun produces so many holes of so varying sizes, let alone that accurately? Or do you mean they randomly unloaded once or was on the ground?
Same kind of damage as on MH17 which was a BUK missile if I remember correctly. It basically explodes near the target like a big handgrenade causing scattered damage like this.