One author not showing in Author drop down list while editing page

the answer is provided here: Users with custom roles not showing in post author select box

I tested and it works:

to add a level_1 cap to your role.

It's PITA, considering how user levels have been deprecated so long ago, but there you go

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)