They speak Yunnan dialect and they can speak Mandarine with accent.

In fact most the ethnic groups have their own Language,which is completely different from any Han Languge.But most of the Minority people can speak Yunnan Dialect,which is a local Han language similar to Sichuan Dialect.
And Young People mostly can speak Mandarine,but not offen used in daily life.

I visited all three places just a few years ago. There was no problem communicating in Putonghua. At the worst, you might need to ask people to slow down.