[판정을 받은 것으로] 확인됐습니다. 으로 in this case indicates a fact or outcome of a judgement or revelation. Since 확인되다 means "is confirmed", X-으로 확인되다 means "is confirmed to be X" or "X has been confirmed", where X is a noun or its equivalent. Your example is using a noun phrase based on 것 (thing, fact). [-ㄴ 것]으로 확인되다 is a common phrase for "It is confirmed that [...]". So, - 판정을 받은 것으로 = that (someone) has received a 판정 (judgement, decision). - 이태원 클럽과 관련해선 지금까지 최소 165명이 확진 판정을 받은 것으로 확인됐습니다. = As for/Concerning the Itaewon clubs cases, it has been confirmed that at least a hundred and sixty-five people have so far been tested positive.