Could a relay chain quietly warn Kido Butai?

Could ships, submarines, or aircraft relay the news to Kido Butai at low power?

In theory, but no such relay was arranged, and creating it would consume assets and risk revealing the operation.

A low-power relay would require properly positioned assets, agreed procedures, and time to establish the network. No such chain formed part of the Pearl Harbor plan, so submarines, ships, or aircraft would have to be diverted and coordinated at short notice. Any relay unit discovered along the route could expose the operation, while reorganizing the strike plan at the last moment would create further risk. The idea is technically conceivable, but the missing preparation and operational-security cost keep it from being a practical answer to Kido Butai's radio silence.