I think you are out of luck, I don;t think you can download it from anywhere else.

Microsoft To Do Download Mac

Maybe also look into http://cord.sourceforge.net

Microsoft Rd Client For Mac
  1. Download this app from Microsoft Store for Windows 10, Windows 8.1, Windows 10 Mobile, Windows Phone 8.1, Windows 10 Team (Surface Hub), HoloLens. See screenshots, read the latest customer reviews, and compare ratings for Microsoft Remote Desktop.
  2. Fixed a bug that caused the client to randomly stop responding when downloading feed resources. Fixed a bug that caused the client to crash while opening. Fixed a bug that caused the client to crash while importing connections from Remote Desktop, version 8.
  3. Thank you for writing to Microsoft Community Forums. I understand that you want to use Remote Desktop app to access/see Azure RemoteApp on Mac machine. I would suggest you to refer the article Get started with Remote Desktop on Mac.

Why don't you try downloading it on your computer and see if you can extract the file from the download? Right-click and show package content.

Get the Remote Desktop client. Follow these steps to get started with Remote Desktop on your Mac: Download the Microsoft Remote Desktop client from the Mac App Store. Set up your PC to accept remote connections. (If you skip this step, you can't connect to your PC.) Add a Remote Desktop connection or a remote resource. Start quickly with the most recent versions of Word, Excel, PowerPoint, Outlook, OneNote and OneDrive —combining the familiarity of Office and the unique Mac features you love. Work online or offline, on your own or with others in real time—whatever works for what you’re doing.

PS: Is that: https://www.microsoft.com/en-us/download/details.aspx?id=465 the right client?
I can't test it since I don't have a MAC at work.

Microsoft Windows For Mac Download

or this one: https://www.microsoft.com/en-us/download/details.aspx?id=18140

Microsoft Rd Client For Mac Client

Edited Apr 21, 2015 at 22:53 UTC