The Church has never made Herself judge over the souls of men. That is Christ's alone and it is His prerogative to welcome us home. The Church teaches us how to live and worship in the Family of God. Those who come to repentance without a chance to enter the Church may experience a "Baptism of Desire" where they would have been baptized had there been time. Certainly, if you follow Jesus's ministry, had their conversation occurred not on the Cross, Baptism would have followed.
Yet to be consistent, this still would not provide them with the perfection of character, and which makes purgatory essential.
There is inconsistency here, as while the newly washed convert is said to be fit to go right to Heaven, yet that is not the same thing as perfection of character, "you must be perfect as the Heavenly Father is perfect", which RCs invoke.
For Purgatory is not to be forgiven, nor simply to atone for sins, but,
"...we will go to Purgatory first, and then to Heaven after we are purged of all selfishness and bad habits and character faults." Peter Kreeft, Because God Is Real: Sixteen Questions, One Answer, p. 224 )
And to think the "good thief" attained the perfection of character needed to be with God in the shirt time on the cross, is absurd. This takes many different kinds of trials, not just suffering.
And it is only in this life which provide it, that growth in grace is taught. Thus even Christ was made perfect through sufferings in this life, though not as attaining moral perfection, but by being tempted in all points like as we are, yet without sin. (Hebrews 4:15)
One either dies in saving faith to be present with the Lord or one suffers in Hell and then the Lake of Fire. See debate here i had a little while ago.