CONGRATULATIONS on a successful nursing session!!
That first one brings such a high!
To answer your questions: Yes, she CAN learn to nurse from different nipples. My DD has had to nurse from me, a nipple shield, a bottle, and a pacifier since 3 weeks. Not all babies do that successfully, not all of them are interested/willing to even try. But it definitely can and DOES happen, so have hope. For us, it just took a lot of unlatching and trying again when she was gnawing. Also, my LC showed me how to 'help' her open her mouth wider.
My state actually has a free public health nurse that is basically THE LC for the area. She's come out to my house weekly since the birth. There's also a free breastfeeding class put on by the state, a great LLL group, and lots of knowledgeable midwives and mothers in my area. Maybe you can try calling around and asking about breastfeeding resources. There could be resources you've never thought of, and maybe more free/affordable options than you expect. I'd try calling a WIC office (they encourage breastfeeding so ours has an LC and they're very knowledgeable about resources), any midwives established in the area, and maybe a good pediatrician or two. Obviously, LLL meetings are a good place to get info too, but sometimes going and watching people successfully breastfeed is painful when your own nursing relationship is so hard. I don't want to discourage you from going, I just want to let you know that IF you're intimidated or discouraged by an LLL meeting, you're not the only one.
Good luck with the latch. Kudos to you for working so hard to give your daughter the best, especially through weeks and weeks and weeks of struggle. It's not easy, and it's not fun, but it sounds like you're doing a GREAT job.