If someone can please explain a few things about raise dead in TWW2:

1. In my Mortal Empires VCounts campaign i had several fights and city sieges with huge casualty numbers (over 6000+ units) that did not spawn any "raise dead marker" at all.
Is there some sort of special requirement that i need to fulfill in order to be certain battles with huge casualties will always spawn the marker (skeleton hand)?
Or it is perhaps purely random will a huge battle spawn a marker or not, so even huge battles with 8000 casualties can spawn no markers at all?

2. It seems battle markers are "region wide", with a region being a small area around each city.
But it feels rather unclear where my army needs to be standing to get raise dead benefit from the nearest battle marker...
Sometimes i get different Raise Dead options depending is my army in the city or does it move 1 step out of that city?

3. If there is already a raise dead marker in a region can a new big battle add a new number of casualties to the existing number?
Or does the new casualty number overwrite the old one if it is larger?

4. Do both the enemy as well as my own casualties count for the raise dead markers?
Can the markers also be spawned by two armies fighting if none of them is mine (or a vampire)?

5. Are all the units offered in the Raise Dead panel on a separate cooldown?
As in if i buy a lot of one unit will it affect how much of other units i can raise dead in the upcoming turns?

6. Is there any way to see when will certain units at a specific RDead marker be available again after i bought them through Raise Dead?