Update!

Sale 1: https://backpack.tf/profiles/76561198350054215#!/compare/1707177600/1707436800

https://backpack.tf/profiles/76561198034154143#!/compare/1707350400/1707436800

13 keys match

Sale 2: https://backpack.tf/profiles/76561198834218821#!/compare/1708041600/1708128000

https://backpack.tf/profiles/76561198382588936#!/compare/1707955200/1708041600

5 keys, Taunt: The Pooped Deck and some random cheap items match = ~6

This could be 24 keys + ~6 = 30, given that keys seem to have been spent to buy these: https://backpack.tf/item/10305619244 / https://backpack.tf/item/13349818068 / https://backpack.tf/item/11098066283

However, while some removed keys on the buyer side match with Harry, this removed item on the seller side also matches with Harry: https://backpack.tf/item/7957579741 additionally to the gained Max's Head.

Calling this trade untraceable.

Sale 3: https://backpack.tf/profiles/76561198373441546#!/compare/1709251200/1709337600

https://backpack.tf/profiles/76561198185816810#!/compare/1709251200/1709424000

Untrace.

Sale 4: https://backpack.tf/profiles/76561198185816810#!/compare/1712707200/1712793600

https://backpack.tf/profiles/76561198841031804#!/compare/1712707200/1712793600

7 keys match.

Sale 5: https://backpack.tf/profiles/76561198373441546#!/compare/1708214400/1708300800

https://backpack.tf/profiles/76561198382588936#!/compare/1708214400/1708300800

Sold for a Miami Nights Murderer's Motif (26 keys)

Mini for the Motif: https://backpack.tf/suggestion/66229a126a71f8bf000ce255

26 flat.