My question is--
if your child won't get high school credit for the course, is it now (or does it seem likely to be) a state graduation requirement that THAT particular course (or, for that matter, geometry) be on her transcripts?
That's the only thing that I'd be worried about, honestly. The rest is all stuff in the future, and meeting your child's needs now is more important either way.
If she is ready now, and you determine that not having that on her high school transcripts is going to be problematic, figure out how to get it onto those transcripts.
That's all. No way would I permit those kinds of considerations to influence what my child seems to need, though. As others note-- IB aside, there is higher mathematics for your child, and you'll figure it all out when you get there.
Could she do online assessments for the course NEXT year after a summer of self-study?
I'm also not completely convinced (having recently seen both geometry and algebra II, and also having a bird's eye view as DD tutors both pre-alg through geometry) that there isn't any dependence at all on geometry within Algebra II coursework.
There's some. But it'd be pretty easy for a gifted, mathy student to figure it out along the way.
