Just as a little correction: Dutch is not an "evolved German dialect". German and Dutch are both West Germanic languages, but so is Scots, Frisian and English. So it would be like saying that German is an evolved English dialect then (though to be fair, Dutch and German are grouped closer to each-other in that family tree usually and have provided a lot of substrate for each-other due to close contact).

Swiss German is not regarded as a its own language by any nation, though from a purely linguistic perspective it could very well be classified as its own language. What is deemed a language vs. a dialect usually comes down to politics. The saying usually goes something like: "A language is just a dialect with an army".