the point was can the vault work, the fact dave remembers everything proves it.
but does that affect the medicine any
Depends:
a) NO: Oswin medicine had always been a succes; the Events on Judgement Day happend because the experiment at the hospital was sabotaged or botched. ->The treasure hunt was created to unlock the password and encourge Oswin to try again.
b) YES: Oswins Medicine was a Failure and -> The treasure hunt was created to unlock the password and encourge Oswin to change the medicine for another try.
It fits with Flora Message for Dave: If Dave and his friend would have known thats impossible to get all the medals on one iteration, why wouldn't have tried. Life is not about Goal, Succes and Regrets, but rather trying/not giving up, making choices and variance.