twin unfortunately there's absolutely nothing you can do. It will go 2 ways. Either it will be a wake up call and she will really work her socks of. Or she will say "Yeah, and......so what" and go back to bed. Labouring the point may just lead to rebellion and a breakdown in communication
All you can do is help if she wants it. I suppose the only thing left open to you is giving her the Uni course entry requirements and say she's not going to be able to do engineering and that she should consider what she wants to do instead - because she's not going to be jobless after school so she may need to start thinking about getting a shop job! Nothing wrong with working in a shop obviously but if she wants a traditional career then she needs to pull her finger out.
One of things you need to eliminate is that it may be a 'crisis of confidence' and struggling to keep up - and the reluctance to admit it. There's no shame in struggling- I know I do at times!!! Admittedly it is way harder to admit it.
I hope you get through to her.
TBH my DD would be totally livid if she found out I had been behind her back and contacted the school, but after some time of reflection she would probably be willing to accept some help - so backing off in the short term may reap the result you are looking for?