How do I modify an ics file in Outlook to set 'Show as' to Out of Office and 'Importance' to None?

Question

This is how I have the ics file written:

BEGIN:VCALENDAR

X-LOTUS-CHARSET:UTF-8

PRODID:

VERSION:2.0

METHOD:PUBLISH

BEGIN:VEVENT

DTSTART:20230523T000000

DTEND:20230524T000000

TRANSP:OPAQUE

SEQUENCE:0

UID:

DTSTAMP:20230518T160857Z

SUMMARY:Test Holiday

DESCRIPTION:Holiday Desc

PRIORITY:1

LOCATION:

CLASS:PUBLIC

BEGIN:VALARM

TRIGGER:none

ACTION:DISPLAY

DESCRIPTION:

END:VALARM

END:VEVENT

END:VCALENDAR

This is the Outlook item that pops up when it is opened:

Outlook Event

I'm trying to get the Outlook item to have the "Show as" set to Out of Office by default and to have the importance set to no importance by default instead of "High Importance".

I've tried changing some of the fields but I've never had to edit an ics file before and I'm not familiar with all of the fields that I should change or use. I've also tried to read this guide https://www.rfc-editor.org/rfc/rfc5545#page-165 but did not find anything.