I don't mean to contradict the wonderful advice provided here, and thank you for responding. But since adrianus provided such a rule, I couldn't help but go back over the Latin to ensure it wasn't the case here - in which case, that is, 'cognoscit' would still set off an indirect statement.
All translations that I found online seem to back my translation up (i.e., translating it as an indirect statement).
E.g.
Fisher (from Perseus): Germanicus meanwhile, as he was returning from Egypt, found
that all his directions to the legions and to the various cities
had been (i.e., adding an implied 'esse' to make it a verb) repealed or reversed.
Jackson (from
here): On the way from Egypt, Germanicus learned
that all orders issued by him to the legions or the cities
had been rescinded or reversed.
Of course, those are public domain translations, though I still think they merit inclusion here. I don't have a modern copy of Tacitus in English to look it up, but I'm fairly confident it is an indirect statement, unless someone is able to perhaps explain why it is not. I understand that the posts above mine translate it transitively - "... [Germanicus]
found/finds all his orders" + abolita/versa used as adjectives/participles ("found all his orders abolished or countermanded") instead of seeing as an indirect statement: "...
found/finds out that all his orders
had been" (with an implied 'esse' for 'had been'); as to
why the latter is not the correct option, especially now given those other translations, would be really helpful.
At the moment, I'm thinking that it is an indirect statement after all, but that the verb of the subordinate clause within that ('iusserat') is not subjunctive but indicative because of the A&G rule adrianus mentioned; I found another reference to that which makes me more confident: "if a clause in the middle of a report in indirect discourse has a verb in the indicative, this means only that the speaker is adding this point at the time that he is speaking, and that he is not claiming that they were part of the original statement. There is one apparent exception to this: that is, when both the original statement and the speaker could be referring to a clear and present fact, then the speaker often puts that fact in the indicative -- but this usually applies to things at hand, things seen or things the speaker could point to." (See
http://classics.osu.edu/subordinate-clauses).
I would love your thoughts on this nonetheless, of course.