Hello OlegIvanov!
Welcome to our forum and thanks for contacting us with your question!
I have simplified your demo a little bit. In my opinion, the map is drawn correctly. I have set a big lineWidth and it looks good. I don't know what you want the end result to be and what you want to show on the map so it is hard to help you precisely. I found that problem is in your custom source data, you have a lot of points with the same key, so I suggest repairing your custom data or using another.
Demo:
https://jsfiddle.net/BlackLabel/z9tq206c/
Let me know if you have any further questions.
Kind regards!