Thanks
@Finale for your response. I dug a little deeper since my initial question and it appears one Reddit poster stated that given an ITIN is applied for using a passport, then when an ITIN is issued, the IRS has the details of both the passport and the newly processed ITIN number for that individual.
What is unclear is how the ITIN number is then reported to the credit bureaus.
The Reddit contributor was adamant that the IRS informs the credit bureaus ‘automatically’ after around 1-2 months, which could explain why using newly minted ITINs may still cause rejections initially.