You can actually split the private ski week to not ski with anyone. You are buying 15 hours of private instruction (2.5hr x 6) and you can work with the instructor to schedule it however you want.How does a private ski week change exposure risk? Because you're not riding the lift with strangers? Serious question.
Now, the obvious group, if you were going to go private for this reason, would be your housemates, right? I'm afraid mine would have to kill me if we were spending 24 x 7 with each other all week.
I have been been sharing private weeks for years. Sometimes I take it together with friends, sometimes we split the days, sometimes we do full days for just 3 days. I don’t like to be in lessons all week long so sharing works for me.