Is it a sin to cover for colleagues who drink alcohol at work if the goal is to prevent them from losing their livelihoods?

These individuals must be advised and warned by Allah, and the wickedness of their deed must be explained to them, with reference to the verse: ﴿O you who have believed, indeed intoxicants, gambling, [sacrificing to] stone altars, and divining arrows are but defilement from the work of Satan, so avoid it that you may be successful.﴾ [Al-Ma'idah:90], and the hadith: "The fornicator does not commit fornication while he is a believer, nor does the drinker of wine drink it while he is a believer." Then, they should be shunned and boycotted until they repent. If they persist, there is no harm in exposing them and informing the household in which they work, because concealing repeated disobedience is an aid to corruption and encourages others.