A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
I think I know my answers, but better to ask than to assume...
#1 A player resolves Restoring the Doji Treasury. I choose to bring an Empty Crevasse into play. Do I get to choose which of my (legal) provinces it attaches to?
#2 I bring Yasuki Otsuka into play and choose to trigger his reaction, targeting a fortification in my discard pile. Do I get to choose which of my (legal) provinces it attaches to?
I think I know my answers, but better to ask than to assume...
#1 A player resolves Restoring the Doji Treasury. I choose to bring an Empty Crevasse into play. Do I get to choose which of my (legal) provinces it attaches to?
#2 I bring Yasuki Otsuka into play and choose to trigger his reaction, targeting a fortification in my discard pile. Do I get to choose which of my (legal) provinces it attaches to?
Yes to both, by extension from various other rulings about Fortifications.