HaKatan is wrong. 2 women with one man is always Yichud. If the two women are sisters, it’s a Machlokes Achronim (the Tzitz Eliezer brings down both Tzdadim in 6:39:21, if I recall correctly).
And Ben, isn’t Ba’aleh Ba’ir enough? I mean, you can always add more reasons by leaving doors open and stuff, but Ba’alah Ba’ir should be Mattir by itself.