There should be other ways to obtain the Field notes.

[Driavna]

I'm closing in on 20 Castrums so far and I just completed my 10th Dalriada run last night. Nothing from Lyon in Castrum, but I did manage to get the Menenius notes from Dalriada on I think my 8th run. I feel fortunate to have been THAT lucky, but Lyon's Castrum drop feels like it will forever elude me. I've settled on one run a day for each place. Hopefully it will happen eventually. lol

Sucks that is something out of your control and I hope at some point SE put a fail safe, all I can tell is that eventually stuff drop. Hope you get lucky soon.