A couple of questions about Errors Unseen quest

[Zavijava]

I read I can get the Chastity's Hideaway Key from Huxley if I pass a 100/136 Lie or 50 Persuade check with Catherine Malin. The problem is that I got only the difficult Lie check, not the easier Persuade. So is passing the Lie check the only way to get the key or I didn't get the Persuade because I didn't meet some conditions?

Apparently there's a npc called Weston Sloan involved with this quest but I didn't meet him at all. Where's he?