if I'm not mistaken you once complained about a challenge that entering the correct solution was more difficult than solving the challenge itself. That seems to be the case with this challenge also.
I am sorry you had difficulties to enter the solution.
'Sencence' seems unambiguous unless the actual solution has more than one…, so in what order should I put them?
It is explained what is meant by sentence - concretely it is stated: "sentence - the whole plaintext of the last image" in PDF. If I am not mistaken there is only one path that gives you meaningful solution - and this path gives you exact order of all words in the whole plaintext. Unless you cut the path into several sub-paths, but there is no indication you should do so. The first image in all parts of challenges contains one continuous path - and this image gives all clues you need. If it was needed to find several paths it would be mentioned in PDF.
Anyway, sorry again for any inconvenience caused - maybe I overlooked something - but as far as I know there should be only one unique solution. There could be a problem if the path was a loop - but again if I remember correctly the path was not a loop in the part 3.