Is money acquired by relatives from work involving negligence or from a fraudulent nationality considered unlawful (haram) due to its acquisition, thus permissible to benefit from, or unlawful (haram) in its essence, thus impermissible to benefit from? And is there room for scrupulousness (worry) in this case?

The employee's salary is permissible as long as he performs his work, and his sleeping during free time is not forbidden if he does not fall short in his work duties. Dealing with money that is mixed with permissible and forbidden elements is disliked (makrooh) but not forbidden (haram) according to the majority of scholars, and the forbidden money is due to its earning, not its essence. The praiseworthy piety (wara') is that which does not lead to extremism and abandoning the permissible, and it suits the person's situation, unlike the dark piety that is inconsistent with the situation of someone who commits overt forbidden acts.