What do you advise someone who is performing Hajj for the first time regarding the sacrificial animal (adhaahi), and should the check for the sheep be submitted at a specific time during the days of Hajj, especially since he prefers "al-ajj wal-thajj" and fears the unavailability of sacrificial animals, slaughterers, or the poor for distribution?

The aforementioned Hadith is authentic, and its meaning does not contradict entrusting a reliable person or institution to perform the sacrifice on behalf of the pilgrim. If you are unable to purchase and slaughter the sacrificial animal (Hady or Udhiyah) yourself, then it is preferable to appoint a trusted institution like Al-Rajhi Foundation, especially since the mentioned company is recommended by scholars in the Kingdom.