It’s hard to say exactly what did or didn’t happen, but it wasn’t TFW who should’ve been maintaining them properly.Sure by oversee I mean someone responsible for the overall operation yes, I certainly wouldn't expect someone hovering over every person to ensure they have done a job correctly.
I would expect such an individual however to be someone experienced with the maintenance work that needs to be done and should be performing random spot checks to verify that the work has been completed correctly.
I agree we won't really know if corners were deliberately cut by CAF or as you very rightly pointed out that an maintenance step was missed. I would however question if they kept the old experienced staff on that nobody spoke up and questioned if the procedures were changed by management? I would hope now however that wherever they end up these maintenance procedures have now been well documented and they can continue with a new TOC for many years to come without issue!
Unfortunately I don’t work at Chester so don’t know the depot staff there and know if they kept the same people or not. You would certainly hope they do they did they would’ve been willing to speak up and not allow something so crucial to be missed.
Yes, the GWR rumours seem plausible and I think they would be a good fit, I’d love to see them have a ‘good home’ where they can be made good use of.