Unfortunately the Wigan Warriers bit is Ebay's fault, that is a category which appears on their listings. Should have been changed a long time ago to be honest.

I presume it was the shirt made for Lam should he have played. Basically the whole squad would have had their shirts embroidered just in case.

that certainly is one possible explanation (in which they should not have stated "played in"). at best case, this is just a case of a lazy ebay posting.

I'd say that stacks up - a friend won the "Shirt Alert" that season and chose Andy Farrell (same shirt as Rads is wearing in your avatar), and his was a medium!