Group key must start with group_ https://www.advancedcustomfields.com/resources/register-fields-via-php/#group-settings. Not using this will have some of the effects that you mention. The field group may or may not be be created and trying to use the invalid group key for the parent of the fields is also an issue. Not sure about your field keys, they must start with field_ https://www.advancedcustomfields.com/resources/register-fields-via-php/#field-settings
