Sounds like a perfect way to lose a lot of business to me.
"Oh, by the way, you owe us £54m because someone else might be able to see their data on your system that's of no use to anyone but yourself".
Personally, I'd pay the £54m. Then pay £46m to find my own way of doing things that didn't involve SAP one bit in any way, shape or form.
"Dear IT guy, please remove all SAP software from the system by 31st December 2017 and replace with an equivalent that has licensing terms we can't be stung with no matter how many customers we open it up to."