Bee has it right...but I have to say that that thread moved a little too fast for me. Sometimes I'd ask a question and had to wade through 6 or 7 pages to see if anyone had answered it yet. Most folks can keep up with it just fine, but I had a little trouble. That may well just be me.... Mixed hatches such as the ones you are asking about cause all kinds of headaches, but I think it can be done.
I hatched Silkies this spring and one of the things I was surprised to learn is that Silkies NEED a slightly higher humidity. I also learned to watch the size of the air cells. If they are too big at a certain points in the incubation, they are losing too much moisture too fast and you need to up the humidity a bit. If the humidity is too high, the size of the air cells doesn't change much, so they are absorbing too much humidity through the shell and you need to back it down. @AmyLynn2374 and @RubyNala97 have very high success rates with Silkies and I believe AmyLynn also hatches guinea eggs. Their thread is here:
https://www.backyardchickens.com/t/1081034/hands-on-hatching-and-help
I believe it was @AmyLynn2374 who wrote the article "Throw away those manuals" on humidity, but she also is a proponent of higher humidity in some kinds of eggs, including Silkies. I followed the advice from her and @RubyNala97 and had my best hatch ever, on shipped eggs that I got from RubyNala. Good luck!