Ok, benefit of doubt
Ignore the word ‘bisexual’ when looking for a wg, the vast majority put that to appear more sexual(?) or risqué.
The reason you get ‘hung up’ on, is because they think you’re an angry wife.
My partner struggled to get her first female encounter, in fact some of her best encounters have been with girls who do not put ‘bisexual’ on the profile.
Not so much discriminated against, just breaking a mold, so it will be difficult.
My recommendation would be to hunt on adultwork and phone girls directly, do not expect results immediately, or throw your toys out of the pram, if you don’t get your way in the first five minutes (like you did here)