I know it's too late now, but why swap the dummy for your finger in the first place?!
If she is less satisfied sucking her own fingers, it's probably because they are smaller and thinner than yours. It's easier to get a vaccume when sucking something larger. Her smaller fingers may well not produce the same air-locked vaccume.
She maybe will like sucking two or three of her fingers together? Or her whole fist. In your position though I would go about reintroducing the dummy. It might not be accepted, 10 months is late for staring a dummy. But you won't be starting using it, so maybe it will work? I know I'd be trying damn hard in your situation.
If you have something against dummies though, maybe she'll suck the corner of a muslin or a part of her teddy comforter? Not as hygienic, but will meet her need to suck.
I know of a little boy who started sucking at the neck of every top her wore, once he no longer had a dummy. This was much harder to wean off, but he clearly had a need to comfort suck. He was still ruining his tops doing past being 10 years old.
I mention this by way of not under estimating the need for comfort sucking in many children. You may be tempted to not provide an alternate for comfort sucking. It may work, but be prepared for baby to adopt something you wouldn't choose for sucking instead.