im sorry Sharon. we all feel your pain, your anger. its enough that we spend any time visiting the loo to have it highlighted as an accusation is only more offensive, uncomfortable.
the irony of course is that the clogged toilet is a fear many of us have faced but to be slapped with an unwarranted accusation, a brown letter if you will is inherently inhumane and creates all kinds of ill will, poor feelings etc.
I guess given the uncomfortable lack of tenure/position and the proximity of the end of the year, perhaps the better path is to move on and away. distance yourself from the unworthy and unfeeling accusers.
keep your head high and imagine a fiery poo bag lit on the directrice's doorstep. hopefully that might bring a smile to your visage, turning that frown upside down.