For UK online gaming source of wealth verification is a necessary and important step. Are there any quality service providers that I could recommend to my clients to meet with and engage with who can conduct this service?
In hopes to point you in the right direction, as it relates to the future of society and business advancements;
A company that has arguably the most potential for drastically altering and revamping the way professionals execute verifications, background checks, and other skillset certification validations etc. etc. - is the wide spreading Smart CARDS. Not the mini cars, but the universal ID Cards that contain your underground pass, you medical records, your financials, and your criminal records. All in one.
Whether or not you feel that is a good thing, is up to you.
I think that it has terrible implications and far greater potential for it to be misused than it would serve as an actual "perk."
Last bit I might add, is that you should look into the fantasy sports & gamer betting app called Dribble, based out of London. Thats the other token I hope will send you in the right direction. Sorry for not having a go-to direct answer for you. Best of luck.