I think it's wise to be cautious about this sighting...as has been posted already, why only now is it becoming public? Why keep that to yourself, when everyone in the area were talking about it for weeks? Unless,
@SnooperDuper 's b) is the case.
I don't think money would really be an issue, though. It would cost, what, $80 or $60 for the PAL, depending if they wanted restricted or non-restricted guns, and $80 for the course. These two could have combined their paycheques for two pay periods for probably close to$4,000 pre-tax. The harder part for these two would be passing the exam, I'd think. They seemed to have learning issues and likely concentration difficulties. Although, when you're keen on something, that desire can really keep you focused. If one or both had a PAL, that'd be known to LE.
They could have just as easily purchased a new or used gun online legitimately, or, as has been suggested, from someone locally and completely unrecorded anywhere.
EDIT: Sorry...meant two pay periods, not two weeks for their pay