(I did mine in 1998 so it may have changed) DST Leconfield wouldn't load you onto a Driving course without passing the theory as they didn't see the point of training you in the practical if you couldn't pass the theory exam, there were loads of people on the 3rd/4th exams who were about to get binned for being mongs. I'd imagine this would still be the case, however someone whos been recently should be able to confirm.
I would expect it would be part of the package, as you take your test at the end of the training you'll need to have completed all exams prior to starting.
Edit to add: Do her joining instructions not mention it? Get her MT/Driving section to confirm, should take a quick phone call.