Perhaps contacting the Microsoft Disability Answer Desk directly would be helpful,
https://support.microsoft.com/en-us/answerdesk/accessibility
I have contacted three times, twice by chat and once by phone. They just aren't familiar with keyboard commands. If you search for Excel keyboard commands, you get E
xcel keyboard shortcuts and function keys at
https://support.office.com/en-us/ar...2b8-9c99-9b7213f0040f?ui=en-US&rs=en-US&ad=US
The only Alt commands for the ribbon are the following:
[TABLE="class: banded flipColors"]
<thead>[TR]
[TD]
To do this
[/TD]
[TD]
Press
[/TD]
[/TR]
</thead><tbody>[TR]
[TD]Open the Tell me box on the Ribbon and type a search term for assistance or Help content.
[/TD]
[TD]Alt+Q, and then enter the search term.
[/TD]
[/TR]
[TR]
[TD]Open the File page and use Backstage view.
[/TD]
[TD]Alt+F
[/TD]
[/TR]
[TR]
[TD]Open the Home tab and format text and numbers and use the Find tool.
[/TD]
[TD]Alt+H
[/TD]
[/TR]
[TR]
[TD]Open the Insert tab and insert PivotTables, charts, add-ins, Sparklines, pictures, shapes, headers, or text boxes.
[/TD]
[TD]Alt+N
[/TD]
[/TR]
[TR]
[TD]Open the Page Layout tab and work with themes, page setup, scale, and alignment.
[/TD]
[TD]Alt+P
[/TD]
[/TR]
[TR]
[TD]Open the Formulas tab and insert, trace, and customize functions and calculations.
[/TD]
[TD]Alt+M
[/TD]
[/TR]
[TR]
[TD]Open the Data tab and connect to, sort, filter, analyze, and work with data.
[/TD]
[TD]Alt+A
[/TD]
[/TR]
[TR]
[TD]Open the Review tab and check spelling, add comments, and protect sheets and workbooks.
[/TD]
[TD]Alt+R
[/TD]
[/TR]
[TR]
[TD]Open the View tab and preview page breaks and layouts, show and hide gridlines and headings, set zoom magnification, manage windows and panes, and view macros.
[/TD]
[TD]Alt+W
[/TD]
[/TR]
</tbody>[/TABLE]