Good.
No issue on phpinfo : all required modules are set : 'mysql', 'pdo', 'pdo_mysql' and even 'mbstring'
Only possible issue with modules is incompatibility of version between pdo_mysql and database, but I really don't think issue is here.
Do you still have error message "Module PDO for is not available - check your php configuration (php.ini)" ?
What is weird is that it should display "Module PDO for mysql is not available".
Error message makes me think that $paramDbType is not set.
What you can try :
1) check file /tool/parametersLocation.php : $parametersLocation will tell you which parameters.php file is used.
Open this parameters.php and check value of $paramDbType (check all file to be sure it is not overwritter in the end)
2) if $paramDbType is correctly set, try and add some debug lines in /tool/configCheck.php
For instance, on line 38, add :