Millions...do you have sources for this?
Of course. For example: "Users of Xapo, TenX, BitWala, and BitPay, which amount to several millions, have been told that they will no longer be able to utilize their cryptocurrency debit cards. "https://www.ccn.com/visa-crackdown-on-bitcoin-and-cryptocurrency-debit-cards-no-big-impact/
Sorry but just saying that in an article is not a source, I was looking more for a visa statements on how many they have cancelled. Small business have a habit of overestimating their customers.
You asked for a source. The one I offered did not satisfy you. Fair enough. Neither Wavecrest nor Visa have offered any information on how much money or how many people were affected, afaik. There is now the possibility that we are talking about millions of people rather than millions of dollars or Euros. Try coming at it this way - imagine one hundred people, each spending one BTC a year on their debit cards. At present BTC value on CMC that would be $1,116,200 in annual transactions. I find it easy to infer that millions of dollars (Euros) in transactions were affected by the Wavecrest cancellation. Millions of people, not so much, but that was never my claim.
Any suggestion for what I need (post above) 
Sorry, I don't. Your situation is very different from mine, but any non-Wavecrest virtual prepaid cards I have stopped working at about the same time as the latest Wavecrest shutdown, no reasons given. C'est la vie. Looks like Samarkand has a suggestion for you though. Good luck in any case.