I've seen a lot of people who severely look down on Civil War as a classic case of having a villain 'who can manipulate everything to be exactly how they need it to be no matter how unbelievable the situation is'.
The truth is if you really look at Zemo's plan, most of the movie's major coincidences aren't *necessary* for his plan to succeed at all. They just happen (because they make for a good movie). He succeeds at slandering the Avengers' name the second Cap (and others) go rogue, which did not require a ton of manipulation. He succeeds at killing the extra Winter Soldiers through simple torture and murder, mostly off camera with no manipulation involved at all. And his (temporary) success at driving the Avengers apart is often interpreted as only possible because of Zemo's 'master plan' to get Tony, Bucky and Cap together in a specific room in Russia. This, according to some, means the movie is ridiculous because 'what if Cap was arrested and only Bucky and Tony arrived? Or what if Tony didn't show up at all?' Etc.
But the reality of the ending is that Zemo very much likes the idea of getting to lecture Tony and Cap in person about Bucky's history, but he's already proven himself willing to just put evidence out on the internet (when he deliberately called a hotel maid into the room where the real psychologist's body was hidden), which would produce the exact same results in terms of driving the avengers apart. Zemo just wouldn't get to gloat over it all before he died. Meanwhile, in the alternate universe where Cap didn't get to Russia, Zemo actually did even better than he does in the movie as written. Tony unquestionably would've killed Bucky in those circumstances and the relationship between Cap and Tony would've been even worse off as a result.
Pretty much all of the specific manipulation after 'frame Bucky' was optional. A great bonus for Zemo to shoot for if he could get it.