He didn't say to put the Oregano Oil on your face, he said to take it in capsule form.
As for sunbathing, as I understand it you start out with just a minute or two at first. I'm guessing that a minute or two won't burn your skin.
As for sitz baths... the water wouldn't touch your face at all. The 108 page that Brent has put up has a page on sitz baths if you need more instruction.
The situation with your face really sounds like a liver issue.
It would help you tremendously to really understand what is being recommended to you before shooting it down. There is likely something offered that can be of benefit.