Ask a deputy
A deputy's phone holds the test key. Show them this phone's code, or send them its text; under Hand out sheets they choose Hand control and get a code or link back for you. Nothing re-pairs, and every sheet synced so far comes with it.
Then take the test from their code or link
Or scan the hand-over code on their phone.
From the cloud with the passphrase
Enter the recovery id shown on the test's dashboard, or paste any invite link you sent for it, and the cloud passphrase you saved under Backup.
From a backup file
Open the backup you shared to your email, or paste its text.
From a judge's or steward's phone
Any helper can show their copy of the test from their screen. A steward's copy has every class. This rebuilds the entries with new keys, so you will need to pair every judge again and they will resubmit their sheets. Nothing they have scored is lost.