According to your save, there is 2, not 3 tanks at that base, both onboard the Zepp. After mission (loaded from the previous save), both are accounted for. Check your stuff before raising alarm.
Yes, you have right. I am sorry, my mistake. But I was 100% sure there were 3 tanks in that base and now I wonder what happened to the third one. And after mission one tank was automatically removed from Zeppelin inventory, because there was no longer ammo for it.
As for missing tank corpses, you don't need to upload anything to YT, just show me any proof of a tank corpse disappearing without a reason. Preferably a save from just before it happens with instructions how to replicate. What I found out was only that all existing (visible) corpses were recovered. I mean I could play the whole mission, but such a problem was never reported so I feel it would be a waste of time.
You see there is a problem. When tank doesn't leave the wreck it happens in moment it is destroyed. There is animation of tank being destroyed and thats it - no wreck. Kinda hard to prove that in that spot should be lying wreck. And missions with enemy tanks in the field are so far rare.
If you are saying that there is no god/spectator mode or console commands and you can't reaveal map to check if there is really 8 enemy tanks in that Siberia mission, then reload save nr 5 from beginning of that mission, wait to turn 2 and exit Zeppelin to scout as much as possible. I have found that way 7 enemy tanks - save exp2.rar. There is isolated island on right side of the map with 4 tanks (only 3 are visible) and if you reload end of that mission (save 2.rar), you will find only 2 wrecks on that island and no sign of destruction that could destroy other 2 wrecks.
And one more possible bug (game ver99J2).
To prevent selfdestruction of engine on supply ship I destroyed it with Asuka rifle. It was gone, but exploded anyway one turn later. I reloaded and on second attempt I destroyed engine with barrel bomb. This time it worked. So, is destruction of engine with rifle insufficient in sense that there must be certain amount of force applied in order to destroy it for good? Or destroying engine with rifle was bugged ?