The compares are likely just broken because the ranges aren't fine enough (as in, they span about 3 weeks instead of a day-by-day history).

Here is the other side of the 1600 trade, but as stated in the original the keys are missing from here (likely for the same reason as stated above):

https://backpack.tf/profiles/76561198153496203#!/compare/1731888000/1731974400

This is the other sale that looks like a cash sale, just for documentation purposes.

https://backpack.tf/profiles/76561198406114836#!/compare/1732924800/1733011200

https://backpack.tf/profiles/76561198153496203#!/compare/1732924800/1733011200

^

If a mod asks for you to use this, you'd just have to add the person and find out what they bought it for. There is a way to do a "mini" on keys in the event of a paypal transaction, but there were multiple things bought and sold so I'm not sure how willing the mods would like to use this anyways.

Regardless, this suggestion seems fine as it is, unless another sale comes around.