Part of the problem is the discrepancy between what eBay feels, and tells sellers, is acceptable - shipment within thirty days of the close of an auction, and what buyers, especially knife buyers "spoiled" to some extent by the normally fast and smooth transactions here, feel is acceptable. That said, in over 200 eBay transactions, I have never had an item fail to arrive. While a few sellers pushed that 30 day shipping time frame to the max, most went smooth as glass and as fast, or faster than anyone could have reasonably hoped for.
If I were in Colog's shoes, I'd probably send another email to the seller at this point asking if there was tracking number for the package. They may be, as some feel, next to worthless for confirming receipt of a package, but they DO prove that "something" was shipped, from address A, to address B, on a specific date.
They can also occasionally highlight a problem that explains a delay in delivery. Have had postal clerks, both at my end and the other, mis-key a ZIP code when they're printing the stamp. Since a lot of the sorting and routing is done on the basis of the ZIP they print there, as opposed to the one on your label, that can send a package a little or a long way out of its way, depending on the digits that are mis-keyed or transposed.
Had that happen once. Ever since then I've been very careful to check my receipt, which lists the ZIP the postal clerk keyed in for the stamp, before I leave the counter. Twice so far I've saved myself, and the folks I was shipping to, some unnecessary aggravation by doing that.