Okay, so this person could not receive the last rites nor the sacrament of reconciliation (confession). If he makes
perfect contrition, he has remission of sins. Perfect contrition means to repent and admit your sin out of your love for God,
not out of your fear of His wrath (the latter being known as imperfect contrition; a person can have both). The Anointing of the Sick, more popularly known as last rites, is important. Here’s what the CCC says:
So without the last rites, confession, or an act of perfect contrition, this man has a mortal sin on his soul. The CCC says on such a matter:
However, there may be exceptions: God may, as He is merciful and loving, grant this man a pardon. Or, the Church may grant him remission of sins. For example, there were so many people dying during the Black Death (1346-1353) that the Pope allowed for remission of sins for the dying because there was not enough clergy to anoint the sick.
(CA source)