Recently I posted where a 1986 newspaper article from Holbrook, Arizona revealed a quote from the then Petrified Forest National Park superintendent that the remains of a basal dinosaur recovered from the park in 1985 would be called "Holbrookosauras smallii". This brought up some discussion of this name as a nomen dubium and that I had been wrong that the name Chindesaurus had been the first unoffical name mentioned for this specimen.
Well it turns out that I was originally correct. There is an article in Science News from May 25, 1985 where the lead paleontologist on the discovery (and future describer) Robert A. Long states that because the specimen was recovered off of Chinde Point and because it is the Navajo name for 'ghost' he may call the newly discovered specimen "Chindesaurus".
This is now clearly the earliest known reference to this name as applied to this specimen and because the interview that is the basis for the article was conducted before the excavation was even completed, it may stand as the earliest. I am still puzzled where the name "Holbrookosauras" would have originated. Maybe Long was going back and forth between the two before finally settling on Chindesaurus in 1989.
This is actually the best article I have read discussing the initial discovery. Notice that the opening line mentions a quadrupedal animal. This is because initially Chindesaurus was thought to be a sauropodomorph and based on the morphology of the astragalus (the first bone recovered), which actually made sense as there are sauropodomorph characters present in this elements as discussed by Nesbitt et al. (2007); however the 'confusing' aspects mentioned by Long are theropod dinosaur characteristics as well. Thus wehen Long and Greenwald are discussing that this may be a link between two lineages of dinosaurs they are talking about sauropodomorphs and theropods. Below is the initial 1985 reconstruction of Chindesaurus as a 'plateosaur' by artist Rick McCrea.
If you missed the above link you can access the article here:
The Patagonian Land Penguin
8 hours ago in Catalogue of Organisms