Oh dear, I almost got stressed just from reading your post lol
For what it is worth… We boarded Sojourn on 21 December for 166 nights. We completed the online check-in ~21 days prior (easy), got the suitcases out 7 days prior, noticed our boarding passes had appeared in Source about 9 days prior and completed the medical questionnaire 3 days prior. We didn’t bother with Verifly, luggage tags or anything else. We had the easiest embarkation ever and life on board is as perfect as ever.
Relax! You’re going on holiday! 🙂