How to match output parameters with input ones in Adobe Premiere?
The option you are talking about matches the export settings to the sequence settings, not to the source material. So my guess is that your sequence does not match your material. You can create a sequence that conforms your source clip by right-clicking on the clip in the project panel and selecting "New Sequence From Clip". Then the export should work as intended.

However, keep in mind that this will reencode your entire video, which will always result in quality loss. If you want to cut out a piece of your video while leaving the rest untouched, you could probably do that with ffmpeg.