Failed verification
Pressure

A source is being mis-used where there is a statement that says the fringe media pressured these various agencies to respond.   

Entry says:Because of the popularity of the conspiracy theory, official agencies have received many enquiries from people demanding an explanation.[1][3]

I think it is dubious and the source does not mention popularity as the cause for this pressure nor do these vague inquires seem to be specific incident complaints of the type these agencies investigate. This would require times, dates, locations, to proof of an incident much less any "suspect" worthy of investigation by the responding agencies.  One caveat is that these are alleged to be CBW issues and an environmental agency, space agency, or weather agency, or FAA would not even be the primary agency to respond, In my opinion, they might be notified or have something forwarded to them if only to answer questions that they might receive.  After enough questions they made fact sheets.  Were the fact sheets released solely because the theory is popular or because of the exasperating questions?  It should worded better. example below:.  Not sure what the dead link said. It's not verifiable.
 
Source states:

This is example consistent with the remaining source:
Government agencies have received persistent questions from people who have asked for an explanation.