my personal preference for handling coffee in a brew is to brew it up at a very high strength. it will gert hot enough in your coffee maker to sanitize it, but that's probably not terribly important since, as you said, the beer will already be antiseptic enough to kill the random nasty.
Oh... and I add the brewed coffee at bottling time until it suits my tastes.
whatever you do, do NOT boil it. it'll taste terrible.