You will probably need a signature to receive the firearm back no matter who they use to return it. If UPS is better for you call Walther and see if they can return it via UPS.Havent sent it yet because I have no way to receive it as a signature is required.
Of course just because a signature is "required" they may not honor that. I've been told by both UPS & FedEx that the driver can leave the package without the signature if the delivery site is deemed "safe'. This was pre-covid.