It is entirely up to you, if you want to ask the officers at the Oath go ahead but I do not think they can do anything for you re the passport (Do not raise the issue before the Ceremony starts
) you never know what can happen). We were told at the Ceremony to apply after two days only, I even went to the passport office the same day to try my luck but was told NOPE, even for Urgent to wait 2 days!
But if you are sure you can apply from abroad then do that, as I said I am not 100% sure the officers at the Oath can help with the passport.
Best,