Also possibly betdaq.co.uk and betdaq.com as well as bestdaq.com which I think is the SE Asian focused version.
You'll find that any company that operates into territories where their product is legal will have a solid license such as a UK one but any that market their product in territories where its use is outside of local laws use 'offshore' licenses such as those from the Caribbean, Costa Rica, Gibraltar, Isle of Man or Channel Islands. This is likely the case with
gamebookers with the Antiguan license being used for US customers.
Its not ultimately necessary as if you're breaking the law (federal wire wager act) in the US anyway there isn't a lot of point having a license but its all about customer peace of mind.