Identify why a historical Core Lightning channel closed
A channel that has disappeared from the active inventory may still have a historical record containing its funding outpoint, close cause and final commitment balance.
Read closed channels for one peer
Set PEER to the public key from the incident record. Compare funding outpoints when multiple historical channels share that peer.
lightning-cli listclosedchannels "$PEER" | jq '.closedchannels[] | {funding_txid, funding_outnum, close_cause, final_to_us_msat}'
Separate cause from settlement
close_cause describes the cause known to the node and can be unknown. final_to_us_msat records our balance in the final commitment. For a cash-flow report, follow onchain settlement and fees separately before treating that number as a wallet receipt.