Hello, not entirely sure what happened but I would add if you had finished your test before the camera got disconnected it should have been fine ( imo) as IRCC says the answers that are completed to that point will submit automatically! However if it disconnected in the beginning like you finished a few questions and came back and finished that’s another story! If it’s the first case send an email providing detail it might work out!
and one more thing as you say you were reviewing it when it disconnected , and hopefully you didn’t change any answers after returning back again on screen, you have a fairly strong case, just argue!