No. Let me put it this way: a self-custodial, liquid-only wallet is not a "self-custodial, Bitcoin-only wallet". A self-custodial, cashu-only wallet is not a "self-custodial, Bitcoin-only wallet". Adding a separate self-custodial Bitcoin wallet to either of these would not change the fact that they are not "self-custodial, Bitcoin-only". They would still be self-custodial, however. If a wallet is self-custodial; but, it is not "a self-custodial, Bitcoin-only wallet", that must mean it's not "Bitcoin-only".