It's not possible to update from Outlook Win32 to Monarch on Azure Virtual Desktop. For the intended purposes using the OWA client doesn't resolve.
Once you toggle the pop up displays it's down...
TaniaMariscal
Microsoft
MicrosoftWe are sorry you are running into issues. To discuss issues we recommend to share your problem on our Tech Community forum (https://aka.ms/wvdtc) or open a support ticket after you have reviewed the troubleshooting options in our documentation (Windows Virtual Desktop troubleshooting overview - Azure | Microsoft Docs)
We recommend to review our troubleshooting section first. The other option you have is to open a support ticket through the Azure Portal.