It's true it will make it more difficult with a diaper, not impossible though. She might even come to like rubbing herself through the diaper even more. You might have to do some trial and error there.
As far as knowing if, or when the tapes have been removed, that can be hard to determine with the newer repositioning style of tapes. But you could try putting something like a small piece of duct tape over the diaper tape. The duct tape will hold, and tare some of the diaper fiber away when it is removed.
If you want to be certain she can't remove her diaper, you can try putting locking pants on over the diaper. These are available from a few outlets, like, http://www.fetware.com/locking-waist-plastic-pants-p-112.html And, http://www.plastic-pants.com/Locking-Pants_LockingPants.htm http://www.ab-versand.de/Penalty-clothing/Penalty-pants/Finnchen-1548.html http://cosyndry.com/products/frilly-blue-rear-locking-baby-pants?set_currency=USD
Those are just a few places to check out.
You might also want to think about using locking mittens for her. Thick padded mittens would severely limit the use of her hands. These can be found at some of the same outlets, and usually can be locked on, so there is no removing them!
Hope that can help you out, good luck, and maybe you can let us know, if you try anything of these, how it works out?