RVU TVs only works on a wired set up natively. DirecTV has change its policy (with good reason) where now all RVU TVs must be professionally installed.
It looks like you are a very new customer based on fee being quoted. You don’t need a client since you are sung your TV as one, but a $49 “early upgrade fee plus a $49.00 install fee amy apply
I don’t see why if you can run ethernet easily, why can the coax be the same….