So littles law applies to dynamic equilibrium where you have a constant number of customers waiting in line for a service
The time it takes to perform the service times the number of customers in line equals the time each customer waits in line
We can think of how long the customer waited in line as the time from when they arrived by train at a concentration camp until when they were executed
Can we think of the number of inmates in the concentration camp as the size of the line
Although the number of inmates waiting in line to be executed might be different on different dates
You can solve this problem by picking two dates where the number of inmates waiting in line were the same
Inmates also might have transferred from camp to camp
You could however look at the time they spent in all camps combined until they were executed instead of the time they arrived by train until they were executed
Eye witnesses say how long it took between each time the gas chamber ran
Now the inmates might arrive into the gas chamber in groups so when calculating the time to perform the execution as the time for the service in littles law you would take the time to run a gas chamber for a group divided by the number of people in that group. You would have to make further adjustments for multiple gas chambers running at the same time.
If between the two dates the same number of people were in the camp(s)
The time between when each new person arrives would equal the time between when each person is executed
Otherwise there would be an increase or decrease in the size of the line between those two dates
When you consider the time each person arrives if they arrive in batches of multiple people on equal intervals then you would have to divide the time interval by the number of people
Now the interesting thing is that eye witnesses testimony might imply that the camps were over crowded and this might imply that the line to execution was not in dynamic equilibrium but instead the time between when each new person arrived was less than the time it took each new person to be executed after they got to the end of the line