Haven't seen any evidence that bookies use iovation for anything other than fraud prevention.
In a previous life I was pretty into iovation and what they can do for device fingerprinting etc.
It's a legitimate aim.
Ofc using it as people are alleging would be bad, and I've seen worrying comments on FB from friends who are traders/compilers in Gib....but still no actual evidence as its use.
I've got a mate who is a fiver and tenner punter.
He's been betting with one of the online firms for 10+ years.
He was at the house of a big punter and asked if he could use his computer. He logged onto the bookmakers site for a bet.
Next time he logged on, he was restricted to pennies.
That is not a coincidence IMO