I was amazed there was no response from Ppruners.
Not much to be said until they look at the data and decide if the fuel control was commanding it or following it.
There are more common reasons for rollback not related to ice in the fuel.
The BA038 thread evidenced unique response of the fuel control not associated with more common causes of rollback.
I'm not saying that the fuel control is causal, only that's a indicator of where to look.