I don't see how anyone could authenticate this item. Other proof would be necessary for me to shell out the kind of money Cobain items bring. If this is legit, it is awesome.
Are you meaning Cooperowen? I have always found their Beatles items top notch but have not heard too much of them lately. At one time, I recall Caiazzo approved all of their Beatle signed items. I am not sure how long that relationship lasted.
After looking at their site briefly, just now, I see at least one piece I don't like.
I do not like this at all. It is not Cobain's writing. I did a quick research. Nirvana was playing at Travel and Transportation Building, State Fair Park, Oklahoma City, OK on December 8, 1993.
Did a quick search on Wells-Roberts Hotel
Wells-Roberts Hotel-Built in 1927 at 15 N. Broadway as the Wells-Roberts Hotel, it eventually became simply the "Roberts Hotel." It was destroyed in 1973 and the space is now occupied by the City Center Building's expansion.