Allah has promised to forgive all sins with the exception of associating a partner with Him (shirk). The only condition for a sin to be forgiven is sincerity. If a person is sincere in their repentance, meaning that they do not go back to the same sin, then that is a sign that Allah has forgiven them. Allah knows best.
Sayed Mohammad Saleh Qazwini
Sayed Mohammad Saleh Qazwini has a BA from the University of Michigan and an MA from Wayne State University. He is a graduate of the Islamic Seminary of Qom, Iran.
We should not conflate the reward of the Ziyaras or Hajj. Performing one does not mean we should not perform the other. Hajj has its specific times and the Ziyara of Imam Hussayn has a specific time. If you can afford to perform both, that would be great. Keep in mind, those who perform Hajj will also have the opportunity to visit RasulAllah, FatimaZahra, and the Imams in Baqee'.
This is a verse in the Quran. (Quran 2:191)