You'll have to go back to a prior save, yes... buuuuuut, there is a system in place where things unlocked on old saves will pop up in your gallery in future saves! No need to entirely replay the game!
Thanks so much for the compliments and the encouragement otherwise! If you can take the time to drop us a rating that'd be super appreciated too, but no pressure~
Otherwise, thanks again for playing, and hope to see ya next time!