Posting the explanation here as well

On 'invalid' sale #1:

You have the sale verified at 97€ received by the seller, which is about 110 paid by the buyer. (its history: https://backpack.tf/item/8442448887 ) - regardless of the graph, you just provided evidence of a sale that will be around 50 keys. In the graphs it is not uncommon to have slight mismatches in date or time due to currency conversions and time zones (especially the former is very likely to be the cause of the value), though I do not know why it displays nov 11 for a sale that early on nov 10, but as I said, you know this sale happened, and you have history and effect confirmed.

The other SCM sale shown lacks effect and history (and profiles) so I can't really do much with that. If you know the person, you could try to get a verification on the effect - if it is this trade then I wonder if AUD is displayed as $ in such graphs, as the amount shown would match the graph's amount in AUD, which would clear up everything regarding this sale.

In either case, this presents you with at least one sale at around 50 keys.

on 'invalid' sale #2:

The rules regarding trades with scammers are very tricky to uphold when they happen through third-party sites such as Marketplace and - to a lesser extent - Mannco.store. We can't really verify who bought them, and for all we know, they were bought by a legitimate person and then scammed, or the buyer directly traded them to a scammer. For this reason, we generally allow such sales even if the history implies they sold to scammers.

Even if this was not the case:

It was still for sale at $100 which makes the suggested value look very high, especially given some of the other sales, including the one discussed above, and the other marketplace at $100.

Furthermore: there is another sale missing: the person that paid 118 (your high end) dumped it later on to the same trader he bought it from in an upgrade which would put its value far lower than any of the other sales seen here. This heavily implies that 118 is an outlier: when the same two traders make two lopsided trades involving the same hat with one another, then neither should be used for suggestion purposes (with the exception of extremely rare conditions which are not met in this case), so the newly suggested high end is not valid.

Lastly: there is currently a seller for ~$150, which not only proves beyond doubt that 118 keys is the outlier here, but it is also lower than the proposed low end, meaning that the new suggestion here is definitely going to be too high.

To summarize:

We now have sales at:

~too low (outlier)

~50 ish (x3, the mp, mannco and SCM sale; exact values can be determined if the suggestion is to be pursued)

~78

~82

~118 (outlier)

A suggestion on this would likely end up around 50-80 depending on the exact outcome after conversion of the mannco, SCM and marketplace sale. The suggested value as it is is going to be too high here, and as a result, this suggestion will have to be closed.

Closing on account of my earlier comment.