"The UAE actively supports Hamas. "
So does Sweden. They just sent millions to the new government there. So do many other countries friendly to the US. Like it or not, Hamas runs the Palistinian Authority, a territory recognized by the UN. UAE is not alone in this support. Support for the political wing of Hamas was not sufficient reason to block this deal.
The same could have been said for Saddam Hussain who ran a territory recognised by the UN and had the support of other nations..