Thanks for the answers. I tried the CoreLightning wallet connection, first it's connecting directly to lightning-rpc, so in case of a bugs/hack LNbits could drain all channels without limits. But c-lightning-rest is the same I guess, until it supports CLNrest with runes.

I still tried to use the lightning-rpc until I have a better solution but it never worked. I run each app by a separate user:group so lnbits cannot access lightning-rpc, even if it's part of the lightning group and the lightning-rpc has 777 permissions. Stuck there, nobody could help in the lnbits telegram as almost no one use it with CLN.