Seems like the homeowner should have kept his big mouth shut. If he wasn’t read his Miranda rights prior to him making them, they may not be admissible in trial.
Yep.
After what he did, his only real option would have been to deep-six the corpora delicti, decommission his security system and destroy all its recordings after a date comfortably in the past, and keep his mouth shut when the cops came around looking for the missing persons (their car was found parked in the neighborhood).