Windows 10, Hybrid O365, Duo MFA login woes

Wondering if anybody else using Duo MFA or another federated login with O365 has been having issues recently:

Starting around May of this year we have been battling a strange issue with Skype for Business where users would get an error '\[..\] unable to retrieve personal certificate \[..\]' We have an ongoing ticket with O365 support with this. The issue seems to stem from never receiving the window to enter the username/password after entering the SfB user. Typically, it should give the 'Taking you to your organizations sign-in page' before loading our Duo Access Gateway login page. Instead we receive the personal certificate error.

More recently (first reported in June, but now thinking related to the Skype error), users are having the 'Need password' issue in Outlook after changing their password. When the user clicks the Need password in the status bar, it shows a blank window (normally would have our login page) and closes quickly.

Researching the second issue, it seems to be related to the Windows 10 Web Account Manager (WAM) and pages talk about adding regkeys for DisableADALatopWAMOverride and/or DisableAADWAM, but neither seems to work correctly or with sporadic success (works sometimes, but unable to consistently replicate).

Our workaround for now is adding the users O365 account to Settings > Accounts > Email & Accounts. The user no longer gets the personal certificate error in skype, or the blank window after clicking Need Password in Outlook. Instead, they do not receive any login prompt at all. This would be acceptable, except that when it comes time to changing their password again, they have to repeat the process.

Most users are on Windows 10 1809, and Office CtR 1902 (Semi-Annual) installs, but issue is also present on Windows 10 1903 and Office CtR Monthly (1908) installs.

Anybody had similar experiences or advice?