A player would be taking chances with the 'Dusknoir' trick. Judge would be within bounds to disqualify a player for dubious game actions intended to deceive.
Making note of what cards you find prized with Time Walk would be akin to making notes of what cards are prized in a deck search. It is not something usually done by note takers, takes time and arguably might not be considered a note about game state. You might be able to do it if you can do it quickly, but you might be asked not to do so by a judge.
Note format is not defined other than they must not affect the pace of play and only notes about game state are allowed. Your notes will be ruled in or out of those guidelines by the judge on site.