I'm not sure you remember your own claim, and you certainly don't understand how it relates to your quote from Hamas. Let me remind you:
In your quote, they explicitly reject any such right. What do you think "from the river to the sea" means? What do you think "rejection of the Zionist entity" means? They suggest they might negotiate for such an existence, but not because Israel has any right to it, only for the sake of "national consensus". In other words, they're signaling a willingness to accept less than what they want. But they're quite explicit in your quote that what they want is the complete destruction of Israel. Stop making excuses for them.