https://carsandcode.com/2014/05/12/oracle-bi-publisher-desktop-on-64-bit-windows-with-32-bit-office/
Personally, until next time, not sure what worked, as above step I did earlier with no resolution.
But, I have been installing, troubleshooting BIP Desktop for few years and each time it is broken, fix do not exist and there are threads which leads to absolutely nothing. This time around, O365 was rolled out to Pilot Users and yes BIP toolbar gone. Uninstalled O365, re-installed Office 2010, repair/remove/reinstall - none worked. Ran MS Debug/ Sysinternals - Procmon/ProcessXP - found leak threads but nothing to suggest which components is missing or corrupted. Finally, I started running all msi and pre-req sw in BIP dir and DotNetInstallFiles, and it did come back the elusive toolbar, which MS Word fails to load or kept in Inactive add-ins.