If I understood your question properly, if two individuals had intimate relationship without intercourse can they marry each other after such haram act?

Yes, they can and actually it is better to do that with repentance to Allah of course from such past actions.

Islam allowed us to enjoy relationships responsibly in marriage and bring tranquility, love and mercy into the relationship.

Zina or adultery is a major sin and it makes people live away from God.

Almighty Allah knows best.