Its not something I have tried but the pure Suite8 way of doing it would follow this guide here:
(the first bit at least), the follow up to that is to look at the accounts detailviewdefs.php and “copy” the recordaction section:
'recordActions' => [
'actions' => [
'print-as-pdf' => [
'key' => 'print-as-pdf',
'labelKey' => 'LBL_PRINT_AS_PDF',
'asyncProcess' => true,
'modes' => ['detail'],
'acl' => ['view'],
'aclModule' => 'AOS_PDF_Templates',
'params' => [
'selectModal' => [
'module' => 'AOS_PDF_Templates'
]
]
]
]
],
This would go in your cases detailviewdefs.php file so copy the detailviewdefs.php file to the appropriate location in custom and then add this section of code. Ensure you have a case template set up (you’ve done that).
Thats obviously two different ways to do the same thing (just in case that wasnt clear), basically you need to add the menu item to the recordActions section to get it to appear for cases.
Regards
Mark