If really necessary I could ask the TOS developers to assist, not sure
whether they would oblidge. Their Master branch build bot compiles twice a
day.
Would it just involve setting a kernel debug flag or something more
elaborate?

You could ask them to build a kernel with dynamic debug enabled

https://www.kernel.org/doc/html/latest/admin-guide/dynamic-debug-howto.html

You can then turn on debugging in a flexible way. And it will be
useful for more than just you.

    Andrew