Unfortunately, WPL plugin uses ‘administrator’ role instead of some user capability in order to protect its menu.
WPL admin menu access

Only users with ‘administrator’ role have access to this menu. It’s not possible to change this editing user roles.

If you send me this plugin copy, I will look into its source code. Some plugins add custom filter, which allows to change how menu is protected.

1)replace ‘administrator’ at plugin source code with some custom capability. Contact plugin developers in order they consider to make the same change with a next update.
2) “Admin menu editor” WordPress plugin, which allows to replace ‘capabilities’ which used during admin menu definition.