Any other tips to help dyslexics?
When I was in college (I went to law school) I wrote a lot. I learned two things from this. First, as a dyslexic I can practice spelling and writing just as I practice my coding skills and improve on my skills. Second, if something, like a legal document, matters a lot, have it proof read by a lawyer. Most documents, emails, etc, do not need a massive amount of proof reading. Even non-dylexic people make mistakes when writing!
Also, if they are customer facing, try and have them use templates when possible to minimize the amount of text to write.
If they misspell things, just try to let it slide and focus on the bigger issue.