Sorry, but your question is all over the place and can’t get clear info on the situation…
Let’s assume – your daughter is now in Australia on a visitor visa and “no further stay condition” has not been imposed – if that’s the case she might be eligible for a student visa.

Bear in mind if you’ll apply offshore and your visa will be refused ou will have no review rights.
It’s safer to apply onshore (if no further stay has not been imposed) – you may get a bridging visa till the decision

Thanks a ton.

Each application is assessed against its own merits.
You may draft your application and you’ll see what documents will be requested.
Let us know if you need an assistance with your visa application.

You’ll have to apply and get permission to travel (Bridging Visa B) otherwise you’ll stuck overseas.

If you do bachelor or masters and will be applying onshore it’s quite unlikely they’ll be asking for funds.
Keep in mind it might take a while before they’ll decide your visa and if you’ll finish your UNI on a BVA before visa decision, they’ll refuse later based on the fact you are no longer registered in the course.

I don’t see the reason why they’d be willing to cancel your visa.
I believe the question here is whether they’ll grant you a new visa or not.
If your level of English was their only concern, and you have provided with a valid test and required score – probably it’s just a matter of time before you’ll see the visa grant.

Sorry to say, but it looks that subsequent applications for student dependants are taking quite long – sometimes half a year or more.
As I am aware these applications are at the very end of the cue. First applications for PHD’s, masters and bachelors, then other primary applications, then subsequent.
Think also about this: possible scenario – when you applied for a student visa – you have left your wife behind to prove you are a genuine temporary entrant, right? Now you want to bring her over. Will you be still considered a genuine temporary entrant?