Is it possible to reset an iPad's iCloud account without losing access to the device?

My grandmother passed away and I have her iPad now. The iPad is tied to an email address that I no longer have access to, as well as a phone number I no longer have access too. I have her icloud username and password, as well as the ability to reset that password because I know all of the security questions, and can see that icloud account on the iPad but since it is signed in using her old comcast address I have not been able to reset the ipad. I logged into the icloud account to try and disable the find my, and it listed no devices... but when I look at devices, it shows the mini ipad. It will allow me to remove the device from account but I am worried about doing that because then I am afraid I will lose all access to the ipad... what do i do??

[Edited by Moderator]