Maybe it's wrong to turn up my nose at a RPG site that breaks even rather than costing money, but I don't blame anyone for asking questions about that first impression. If "OGN", whoever that is, claim it's an SRD for Mongoose's game content, it must have an OGL, so where is it? If it's properly licensed, that document will name the source. "Traveller System Reference Document Copyright © 2008, Mongoose Publishing" is the first edition.
Reddit reminds me that Citizens of the Imperium links to a copy of the Traveller Development Pack. Apparently that's spam-like.