Azure Front Door URL rewrite to display pages from microsite hosted in different domain

We have a website (https://www.example.com), which is load-balanced using Azure Front Door.

We have a microsite (https://www.microsite.example/), which hosts some informational pages.

We now have a requirement to load the wellbeing site pages through the main site URL. For example: if the user types in the URL https://www.example.com/wellbeing, the browser URL must remain the same. However, we need to display the wellbeing site pages.

I added a rewrite rule in the ruleset configuration to implement the above requirement.

Rule details: 
Action: Url rewrite
Source Pattern: /wellbeing
Destination:/www.microsite.example
Preserve unmatched path: Yes.

The rewrite fails, and when I look at the logs, I can see the origin value requested as: https://www.example.com:443/www.microsite.example/.

Screen shot of the ruleset:

Is this requirement possible. How can I rewrite the URL to a different domain without changing the browser URL?

I found the answer in the below stack over flow question. The answer provided by @[Pirmin Rehm][1] worked for me. I have upvoted his answer in the original question.

URL Rewrite in Azure Front Door (Preview) Standard/Premium

I have also pasted the rule I setup in my instance: