You forgot to say what operation you were trying to do.
If it's find in files then the help file says
Exclude - Paths, files, or file types can be excluded from a multi-file search by specifying them with wildcards or full path names. To specify multiple patterns, separate them with semicolons (colons on UNIX). No files are searched in a path that is excluded, including any files in sub-directories beneath. See examples of exclude patterns, below.
So *.git* should exclude any path with .git in its name. If it doesn't work you could report it to SlickEdit Inc and maybe get a hotfix.