The guy behind the organisation, Keith Raniere, used to run a pyramid scheme (calling it a 'multi-level marketing' company) under the name of Consumers Buyline:
https://www.culteducation.com/group/907-nxivm/5968-consumers-buyline-of-clifton-park-was-forced-to-close-after-25-separate-investigations-.html
When that was forced to close it seems that he sought out another way of getting money out of people, in the form of NXIVM (which also calls itself a multi-level marketing company). People like Richard Branson have attended NXIVM events but have avoided being drawn in by the hype. Others though have lost a LOT of money:
http://www.macleans.ca/economy/business/how-to-lose-100-million/
That's aside from the latest allegations, of course. However they fit neatly alongside the idea of Mr Raniere being both charismatic and controlling.
I'm unaware of any UK organisations which link multi-level marketing to cults (or pseudo-cults) but cults themselves are ever-present here:
https://www.vice.com/en_uk/article/wd49g9/uk-cult-information-centre-interview-202