I think its a home built from somebody with above average skills. Maybe it was from a very short lived company even but it is not refined very well like a production product usualy is.
Wood framing is nothing new. Many cars where built that way. The MG's are a good example.
That MG has a lot of wood that the sheet metal is attached to to form the main cabin.
That camper having a wood under structure is unique but not an unheard of or unsound building technique. Wood after all is pound for pound stronger then steel. Just a matter of know how to build it. The desgn looks quite sound just very labor intensive compaired to what you can do with extruded aluminum ribs.