Mathematically, Newcastle have not passed the UCL because they still meet Leicester City, who are struggling to avoid relegation, and Chelsea, who could qualify for Man United or Liverpool.
I don't know how you see it and what kind of calculation is used as a benchmark for whether or not to qualify for the UCL. Isn't it obvious that the top 4 will qualify and now Newcastle has an ideal distance of points to stay afloat. Then with the remaining 2 matches they have that will determine them as a club that passes. Leicester City and Chelsea don't have much hope and both of them will find it equally difficult to conquer Newcastle, so far the strength and solidity of Newcastle's players are superior.
Newcastle game with Leicester City and Chelsea won't be tough at all, this is a game they will have full points that will make them to qualify for champions league next season. Leicester City are in the relegation zone and struggling on how to win their games, Chelsea Is still a struggling team that Newcastle is fit enough to defeat. Newcastle being part of top four in the league have been sealed, I don't think they will lose their position.
The last games of the season are game you don't want to Joe around with, every game at this stage seems like a cup final both for those fighting relegation and those for the Champions League position.
Newcastle might still not even defeat Leicester City but I'm not to make such prediction, Leicester be looking blunt ASF and they have no hopes of escaping relegation currently.
Chelsea might be in a bad position,but you have to believe me when I say that winning Chelsea will be hell difficult for Newcastle to do.