All sites such as 1xbit / 1xbet / melbet and now also kawbet are white label platforms. The underlying software is provided by the company BETB2B.
That means that kawbet does not own this platform, but only manages it. Against payment of a commission, these services can then be used, and no platform itself needs to be programmed.
So that might means that the owners of the 1xbit platform and the kawbet platform do not know eachother at all. But it is an option that it will be the same company behind it, since 1xbit has a very poor reputation accused everywhere.
But the real problem is that withdrawals in this case have to be approved by Kawbet and BETb2b. If one of the sides does not approve your withdrawal, then you can see goodbye to your money.

By the way, I am not using this white label solution. I know this because I read a lot about it and meat these people from BETb2b on an event from IGB.