The born again, have already received Eternal Life.
The Born again are already "seated in Heavenly Places"..
This is the greatest Prize, of all.. as its the "Free Gift of Salvation"...
So, your verses, are not related to going to heaven, or to earning salvation.
They are related to SERVICE..... as in "present your body as a living sacrifice to God, which is your reasonable SERVICE">...
And that Service, is on a "course", that is going to earn down here, what will be given at the Judgement seat of Christ.
Your verses are referring to a CROWN, that some will achieve, after they are born again, regarding their service that is found on their "course".
Your verse speaks of "mastery"., and this is referring to becoming "as many as be perfect", as "the fullness of the stature of Christ" as Paul teaches.
The very first step of this Mastery, is to "work out your salvation".........and that is to finalize this as.... "establish your HEART with GRACE".
So, Crowns are given in heaven, based on mastery of the walk of faith, service in the work of God, and also for never being a person who loses faith.
Being a "Castaway"... is someone, is a born again Christian.......... and this one, is one of those who never became "grace" centered in their walk of Faith, and so, they became a victim of man made false teachings, that took over their mind, and they became lost in these heresies. And Paul teaches this as "subverted within themselves".....they are non-recoverable.. They are too far gone into whatever heresies they became involved with, .. .they became so hardened within their false belief system, so deeply deceived... that they are going to die in that mindset that the NT refers to as a "stronghold".
This is the "castaway".. its the unrecoverable Christian, who is so lost inside false man made heresy, that they will never recover unto truth again, regarding Paul's Doctrine.
Paul says of these, that the are to be kept out of the local church and denied any chance to spread their heresies unto church members.
They are to be locked out.