Looks like it will really do the job.
I use my Moko adjustable case. It doesn’t do flat but near enough. This is occasional use set-up.
(off topic) Bought these from Amazon… for reading and using with a separate keyboard. Holds my 10.5" in its case… Stands up to slide typing and general finger poking better than i expected. $18 US — Got mine for $10 on a lightning sale
Lamicall