Tbh I didn’t read this thread, too lazy. I just read the last few posts so if I’m off with the facts, oh well ...
If it’s a question of desire (lack of her desire thereof), no overt negotiation should take place.
You can’t negotiate (her) desire. Instead, you S & D her. This gives her space whereas either of two things will occur: 1) her desire will grow and she will reach out to him; or 2) her desire won’t grow and that will be the end.
Either way it’s a win win, and the most effective way to approach a girl with lower desire.
Remember fellas, desire grows in space, not in circulation.