With this one provided by Xergoyf

https://backpack.tf/profiles/76561198841279602#!/compare/1591920000/1592006400

https://backpack.tf/profiles/76561198260651783#!/compare/1591833600/1592006400

https://bot.tf/stats/listings/4WX38J9N

Likely sold for ~5 (one of your untracable sales)

Bot.tf says it was 5 keys and 1.11 refined

I can only find the 1.11 refined that matches, 2nd item stack from the top

Then it looks like the Flammable Flippin was bought for unknown amount

https://backpack.tf/profiles/76561198827187707#!/compare/1592006400/1592611200

But no other 5 keys matches in the seller compare

However, one key leaving the buyer compare does match

https://backpack.tf/profiles/76561198260651783#!/compare/1591833600/1592006400

https://backpack.tf/item/3852727396

And in the Flammable Flippin trade, that key goes to a bot that matches with the Strange Classic

So that key went:

spent for spooky i see you

spent for flippin awesome

spent for strange classic

So at least that shows that the key went towards the taunt and explains why it doesn't show in the spooky i see you compare

//

that being said, the sale above is still mostly untraceable as far as compares go, we can just go with the assumption that the trade was 99% 5 keys + 1.11 refined

And other than that, no other 5 key sales are traceable either

Is that assumption enough to say the sale was 5?

Worth noting that a new 5 key buyer is here, now 8 days old (8/12/2020)

https://gyazo.com/1ea94b42da8b2c1a9cc47c88aec4493a

Additionally, no other sales since the July 12 Marketplace sale have occurred

sellers on Marketplace still $11.99 https://gyazo.com/697d27603de64e426572bebcf7892d82

(about 6.5 keys)