Confused about Katyn forest death count

[Lagami]

Hey,

I've recently looked into the massacre of Katyn forest.

In different sources I do read of either 4400 corpses that have been dug out OR of around 22000 corpses.

Are the 4400 the ones that just have been found in the forest and the 22000 are the ones that have also been found around Katyn?
Why do people differ between the ones found in the forest and the ones found in other cities as well so much? What makes the "forest count" so outstanding?

[Karelia]

https://en.m.wikipedia.org/wiki/Katyn_massacre

22.000 is the total number of the Polish officers and intelligence murdered by the soviets in 1940. The murders happened in different locations, of which Katyn is the most famous one. Thus when talking about the "Katyn" massacre people often mean all these murders.

AFAIK 4.400 is the number of the victims in Katyn forest only.

[Ivan Denisovich]

According to Timothy Snyder Bloodlands 4410* people were killed in Katyn forest, that is all prisoners from Kozielsk camp.

As for nearly 22 000 corpses - Snyder says that total number of victims was 21 892 polish citizens**. Apart from Katyn forest they were killed in other places like Kalinin and Kharkhov.

*T. Snyder, Bloodlands, s. 159 of polish edition.
** Ibidem, s. 159, 160.