No you have never seen an exact level and this whole story is greatly overblown (because it is so darn colorful, with a catchy title).
The entire account known to the public is based solely on the book "The Radioactive Boy Scout" by Ken Silverstein. The only reason why anyone has ever heard of this case is because of Silverstein. No statements about actual radiation levels are found anywhere in the book, what you are reporting is pure rumor. And if you actually read the book several things become clear.
First, there is little physical evidence for Hahn's claims. His whole "reactor" assembly, such as it was, was reportedly thrown in the garbage and disposed of without any outside party ever examining it, so his claims about it are without any substantiation.
Second, Hahn was a rather unstable character, and was prone to lying and stealing (by self-confession) so his accounts must be viewed with some skepticism. The whole affair came to law enforcement attention because of Hahn acting strangely late at night in public, drawing the attention of police, whereupon he started to tell them his bizarre tale. They took him at his word, called in the Feds, and once the investigative snowball starts rolling it tends to keeps rolling.
Third, yes, the EPA did come and dismantle his shed in hazmat suits, but the use of such suits is standard procedure so it in itself proves nothing about any actual hazard, and indeed the fact they did it all also does not prove any substantial hazard - CYA is a real thing. The incident itself does not show up as a significant action in their records (in fact the incident cannot be located at all in on-line government regulatory actions for that time and area).
Fourth Silverstein had a book to sell, and he flogs the story mercilessly. Most of the claims made about his case are actually made by Silverstein himself, which he puts into the mouths of people he interviews by asserting things without evidence (other than Hahn's questionable word), and getting them to discuss it based on the premise that what Silverstein tells them is true. Thus the story gets a veneer of having verification which it actually lacks. There is basically no corroboration available for Silverstein's (or Hahn's) claims.