As you probably already know, these “all cash” buyers are often leveraged. Just because they aren’t using purchase mortgages, don’t be fooled into thinking they are actually using 100% unleveraged funds.
With the exception of the previously addressed Blackstone debt, I see nothing in any of those articles that would support what you said. Some are using cash, (a much lower % btw, than has been thrown around by some on this board) and some are financing their transactions. But none are claiming (pretending?) to be all cash buyers, and subsequently financing the properties. At least if they are, it hasn’t been reported.
And I’ve seen nothing anywhere about redemption rights of investors.