Even though Victor isn't known to be an Ally to the LGBTIQ+ Community he is a great writer and artist non the less and liked Vianden so much he stayed there for some time.
3 key dates are the numbers we are looking for this time,
3 key years where he visited Vianden.
When was that?

Send the numbers to the Pink Chest Keepers, write them down as a backup in your book and turn to the next page.