QBO Invitations Blocked

QBO Invitations are being blocked from our email servers due to anti-spoofing policies. So far I have three different mailservers they are coming from to try and whitelist, but it is always different and they do not match any of the mailservers listed on Intuit support pages. The mail servers I have seen so far:

o3.sg.n.intuit.com (168.245.70.213)

b238-234.smtp-out.us-west-2.amazonses.com (69.169.238.234)

o5.sg.n.intuit.com (198.37.158.59)

I have referenced the following help articles and they are out of date/incorrect/unrelated.

https://quickbooks.intuit.com/learn-support/en-sg/manage-customers-and-income/3-solutions-for-when-customers-aren-t-receiving-your-emails/00/382588

https://quickbooks.intuit.com/learn-support/en-us/manage-intuit-account/unable-to-receive-intuit-email/00/369275

https://quickbooks.intuit.com/learn-support/en-us/invite-users/what-to-do-if-invited-users-did-not-receive-your-email/00/185600

Can anyone please provide the current mail servers that QBO uses to send invitations out?