Dan has to be truly nuts. Anyone with half a brain could determine that no typewriter from the 70’s could produce such a document - that exactly matches the results of a modern computer using MS Word...
The documents were such obvious fakes that it is absolutely amazing that anyone at all was taken in by them.
But he might have gotten away with it. All the faker had to do was set his computer font to “Courier”, which in the 1970s was the most widely used typeface for government coorspondence, and that would have solved the problem.