FWIW:
I’ve confirmed these errors occur whether I’m using PHP 8.1.27 or I’m using PHP 8.2.15.
And I’ve confirmed these errors occur whether I select FastCGI or I select FPM.
HTH,
Eric P.
UPDATE: I just noticed that on the previous site on the old server even though I’d specified the FULL name of the installer (http://EXAMPLE.com/20200610_EXAMPLEorg_AFTER_c2193158be6df9376875_20200611035230_installer.php) the installer redirected me to http://EXAMPLE.org/dup-installer/main.installer.php
Does that seem right?
HTH,
Eric P.