I don’t know if there are terms for the positions, but it seems pretty obvious that this is just a question of how you define “right choice”. Not playing the lottery was the choice that seemed to maximize your utility given your knowledge at the time. Playing the lottery was the choice that actually maximized your utility. Which one you decide to call “right” is up to you. I think calling the former right is a little more useful because it describes how to actually make decisions, while the latter is only useful for looking back on decisions and evaluating them.
I don’t know if there are terms for the positions, but it seems pretty obvious that this is just a question of how you define “right choice”. Not playing the lottery was the choice that seemed to maximize your utility given your knowledge at the time. Playing the lottery was the choice that actually maximized your utility. Which one you decide to call “right” is up to you. I think calling the former right is a little more useful because it describes how to actually make decisions, while the latter is only useful for looking back on decisions and evaluating them.