Does praying in the company's prayer room invalidate the prayer or make the worshiper sinful if he does not go to the nearby mosque? Is he obliged to go to the mosque even if his manager refuses? Who bears the sin in this case? Is compensating lost time with overtime considered a sin by taking away the children's rights?

Congregational prayer is an individual obligation (fard ayn). It is valid in any designated prayer area (musalla), and a mosque is not a prerequisite for it, though it is preferable. Therefore, there is no harm in performing congregational prayer in the workplace's prayer area, and it is not necessary to go to the mosque unless permitted by the manager and without harming the work. If the manager grants permission and the work is not negatively affected, then there is no harm in praying at the mosque, and there is no obligation to make up the time. If you do make up the time out of piety, that is good. This does not constitute a neglect of your children's rights as long as you fulfill your duty of providing for them and raising them.