Appears that Deadlock is still using the figures from PRB's initial 43-101 (0.7MM oz. Indicated, 3.4MM oz. Total). The updated 43-101 numbers would show PRB's undervaluation to be in the extreme.
http://www.stockhouse.com/Community-News/2012/July/27/Junior-gold-valuations-average-$38-per-ounce--Stoc