Is it possible for them to never find out about the bite?
 

I know that if you pass out and have people with you, they tear off your sleeve and everyone (with you and at the house) will find out. But if you go alone, and don't cut your arm off, and keep the sleeve down, do they ever find out about the bite?

Haven't tested that out yet, they'd probably connect the dots when they started to see Lee turn more and more ill.

Yeah, I think so. Lee probably tells them when he meets up with the rest of the group at the mansion.

He comes back with his sleeve rolled up and they notice it.

lol, really? I thought maybe they would see it after he faints in the attic, providing he didn't cut his arm off.

If you go alone what happens is you pass out etc and when you get back to the mansion and help them out of the shed thing where they had been locked in, you tell them. They do all find out eventually as far as I'm concerned there is no way for them to not find out.... I'm about 99.9% sure anyway :)