Hi jabcat and taffy,
People confess Jesus as Lord all the time, but that does not mean they are saved. (Matthew 7:21-23) They are religious people who acknowledge Jesus in their head, but not their hearts. Even the demons acknowledge Jesus as the Son of God before he casted them out of the demon possessed, but that does not mean they are saved..just acknowledging who Jesus is.
I believe God can do all things and if He decides to save people after death He is certainly entitled to do so. But.... I have yet to find a scripture in the bible that supports unbelievers being granted repentance and faith after someone physically dies. Therefore, I believe it is appointed for man to die once and then comes judgment. (Hebrews 9:27)
Your trying to connect Romans 10:9-10 and Phillipians 2: 9-11 together and they are talking about two different subjects. Romans 10:9-10 is talking about the way of salvation. If you confess with your mouth and believe in your heart..you shall be saved. Paul has already established in the previous chapters that justification is by faith alone.
Phillipians 2: 9-11 is not talking about the way to salvation, but everything and everyone bowing down before the Lord in acknowledging who He says He is... King of kings and Lord of lords. Some will do this willingly ( Believers). Some will do it unwillingly (Unbelievers, Devil and his demons) Believers will be bowing and confessing willingly and joyfullyto their Lord and Savior. Unbelievers will be bowing and confessing unwillingly and painfully to their judge. Either way all will bow and confess, but this in no way converts the unbelievers, the devil and his demons.