How can I validate the integrity of a torrent retrieved through DHT?

I've just downloaded a dataset made available through BitTorrent and (at length) transferred it to my home PC. Now I want to validate that nothing's been corrupted along the way. Unfortunately, the source of the dataset only provides magnet hashes, not .torrent files - which I've learned is where the checksum information is. Is there a way I can look up a particular magnet link in DHT, retrieve the metadata for the torrent from the BT network, and save said metadata into a .torrent file so I can then use it for local verification? I realize I could also just fire up a BitTorrent client on my home internet connection, but I've heard too many scary stories involving legitimate/scientific/etc data and lawyers etc to want to do that. (Long-tail/edge-case FUD, maybe, but still.) (FWIW, OpenVPN/WireGuard and then locally-based BitTorrent are squarely on the agenda once I master per-process default routing on Linux.)