If indeed your supposition were the case, then the matter would be one to be settled between the two neighboring states. Involvement by the BLM seems both unnecessary and intrusive.
To say nothing of the apparent greed.
The BLM siezed 140 acres back in the early 80’s and Henderson lost a law suit over the matter. This is indeed the dispute I was thinking of. It involves the Red River border between Texas and Oklahoma which was an issue in 1922 when the SCOTUS attempted to settle the matter with wooden stakes in the river bank. Been discussed a whole bunch two days ago here:
http://www.freerepublic.com/focus/f-news/3147020/posts