Welcome to the forum. I hope it will be helpful to you.
Lia used you both, and that was wrong of her. That is the downside of being deceptive and out for one's self-serving purposes. I am sorry you and your husband are hurting. It is good that you were able to maintain a friendship, but I would not want to be friends with somebody like that.
If you and your husband both enjoyed, I see no reason why you cannot continue on this journey. Just be cautious of red flags. Lia never set boundaries but expected everybody to magically understand what she wanted and expected. Confusing and taxing for all involved. Chalk it up to a lesson learned and learn from it. From here, you can figure out what steps to take now. Do you want to seek another couple, or do you want to try individually dating? You had an unfortunate start, but I am positive that it will work out for you both. Good luck!