Head of CDF declares Catholic bishop isn't

[Old Salt]

"without a hint of a doubt that it's valid because Holy Mother Church has decreed it so."

Gerard,
How do you know this with absolute moral certainty?
[referring to SSPX absolutions being always valid]

Certitude is either absolute or moral.  Absolute certitude is not possible in this life, therefore, based on my best and honest discernment, I have moral certitude on the issue. 

And I didn't say they are always valid, because you still have to hear the proper absolution if you are suspicious of such things. 

You said "without a hint of a doubt".
This would obviously include absolute, and moral lack of doubts.
Without a hint...

You are not sure.

No. Moral certitude does not mean a person has doubts.  It means a person could objectively be wrong but can act in good conscience.  Absolute certitude means there is no possibility for error. 

Doubt isn't even relevant to the discussion except in my reference to its absence.  

So again, you are not sure.