This is certainly wrong. The historical ratio of 1 killed for every 3 wounded, isn’t followed here and the fact is, that is way too good a ratio for the incompetent Russians.

1st anyone in an armored vehicle (3-11 personnel) hit by a smart weapon or mine is unlikely to survive.
2nd the Russian medical corp. is poorly supplied and trained.
3rd Russian human wave attacks leave large numbers of wounded on the battlefield to die from lack of quick care.

Given these realities Russian killed to wounded ratios are closer to 1 to 2 rather than the 1 to 4 stated by the intelligence analysts used to American ratios. Authoritarian militaries don’t care about saving their soldiers, and treat them as cannon fodder.