Here's something that might be an improvement or a bugfix, depending on how you look at it - the nanny wasn't properly handling destroyed transforms.
Added .pidb to the list of ignored files
BUGFIX: Improved Nanny handling of destroyed transforms
Previously Tween.update() only checked with target == null, but in the
case of Transform tweens it is necessary to call the reference's Equals
method to ensure that we get the proper answer.
I had no clue null didn't mean null in some cases!
Hehe. The thing is, your object transform reference is still not null, and is pointing to whatever the Unity Transform object is. I expect that when a transform is Destroy()'ed, they set some internal value on Transform to null, and have overridden Equals to verify if this value is null or not.