I, uh... what? You ask "what agencies", then when are told what agencies, are told not to bother trusting them anyway because of earlier things? So why did we even bother answering your question? And if you're citing a fringe lunatic website solely because it's a fringe lunatic website, how is that any different from trolling?
... There's also the point of why Operation Gladio existed. It wasn't set up to interfere with European politics, it was a network of local military agencies which were preparing to withstand a Soviet invasion of Western Europe, and the whole plan of
covert resistance units was based on the WWII French Resistance to NAZI occupation. You just don't publicly state who is and is not a member of The Resistance, because that just ensures that they'll get found out during the invasion and arrested and sent to The Gulags. Clearly, local leaders
did actually know about it, but everything was deliberately kept off the record, because the plan was to spring into action if Stalin invaded and took over Germany, France and Italy. The Soviets would have all the official records then, so none of this stuff could be written down.
The whole plan was put together when Stalin was still alive and around the time the Berlin Wall was going up. At that time, the entire thing was a completely reasonable precaution.
And while there's evidence of
local members of the police or military involved in corruption who also happened to be involved with Operation Gladio, there's really no evidence of any outside actor influencing things. The actions of Gladio units in the different countries were widely divergent and all based on local political differences. For example, the French would have drawn largely from existing French Resistance contacts, whereas in Italy, they drew mainly from anti-communists. And Italian anti-communists in the late 1940s tended to be ex-Mussolini guys. As a result: you had big fuckups in Italy (Which is why we know this as "Gladio" and not the actual name of the program), and no incidents whatsoever in France.