the first question is answered here inside a yellow box with a warning sign: https://cluster.ipfs.io/documentation/deployment/bootstrap/
The trusted peers list is for cluster peer IDs, not for IPFS daemons. The ability for the IPFS daemons to connect to each other will depend on their need and setup, but they might be able to autodiscover themselves on a LAN or via the main DHT if they are on the public network.
If you actually meant the IPFS Cluster daemons, they will try to autodiscover each others on LAN (using mdns like IPFS). Otherwise you need to provide full multiaddresses in the peerstore file or in the
peer_addresses setting in the
service.json configuration, as documented here: https://cluster.ipfs.io/documentation/deployment/setup/#the-peerstore-file