Why? SaRa is intended for limited problem cases.
SaRA- Fix Outlook and Office 365 problems with Microsoft Support and Recovery Assistant for Office 365 – Error during Install / cannot activate
https://diagnostics.outlook.com/#/
This is a Trouble shooting tool specifically for Outlook, with a minor support of Office install problems
SaRA runs tests to figure out what's wrong. It can fix many problems for you, or it can tell you how to fix them yourself.
Trouble setting up Office
I get an error when I install Office
I can't activate Office
Problems with Outlook
Go to the SaRa page
https://support.office.com/en-us/article/about-the-microsoft-support-and-recovery-assistant-e90bb691-c2a7-4697-a94f-88836856c72f
At the bottom there is a section about how to submit feedback. Ask them for a silent install mode.
This page has "command line parameters" for all of the main Office applications. Look in each one for the "silent install". I looked in word and did not find one.
https://support.office.com/en-us/article/Command-line-switches-for-Microsoft-Office-products-079164CD-4EF5-4178-B235-441737DEB3A6#ID0EAABAAA=Excel
MS often reuses components in Office. If you are lucky, they will reuse a "silent install" mode from another Office application.
Here are a couple of links for doing silent install in Office. See if any of the techniques they suggest work. Google Office Silent Install to find more.
https://social.msdn.microsoft.com/Forums/windows/en-US/c8ef3e21-97a9-4777-9b9b-dbc18dc0abf2/how-to-install-with-silent-mode-visual-studio-2010-tools-for-office-runtime
https://community.spiceworks.com/topic/2106044-office-o365-silent-unattended-install
I also took a look at the MS Office Deployment Toolkit. Unfortunately it does not mention SaRa. You could ask them to make an enhancement to add it to the toolkit.
https://docs.microsoft.com/en-us/office365/troubleshoot/administration/product-ids-supported-office-deployment-click-to-run