I'm struggling to understand why the manufacturer suspended the use of Kathlon, especially when doing that leaves EU operators with no approved biocide treatment.
It wasn't the product that caused the problem, it was gross misuse of it.
Failing a technical reason, perhaps the manufacturer's insurer is behind it?
On another topic, I hope that the "on-going AAIB investigation" includes a systematic MEDA (or equivalent) analysis of the Human Factors involved, for the industry's benefit as well as the AMO concerned.