You can always mask every character, including single or double quotes, by using their ascii-code:
char(39)returns a single quote:'char(34)returns a double quote:"
To find the ascii code, simply look for it with ascii(): ascii('a') returns 97. To find the ascii code for single quotes, enter ascii('''') - this returns 39.
Thus you can also use:
CASE
WHEN "NAME" = 'WILSON' || char(39) || 'S' THEN '0,75,224'
END
char even works for Unicode codes:
char(19123)returns䪳, the symbol coded 19123 in Unicode.