Firstly: You mentioned in the comments that this situation is in Mexico. So I'm guessing the common language at the office is probably Mexican Spanish. From what I've seen on this forum, it looks like most of the people here are not Spanish speakers, and asking what the right way to ask your boss about a company finance issue probably has a lot less to do with word choice and a lot more to do with cultural/linguistic nuance, which might be hard to get here. You are probably a lot more knowledgeable about what is/is not acceptable to say in Mexican Spanish to your boss than any of us here. So I'm not going to answer your question directly, and probably neither will anyone else here.
That said, I think you may be asking the wrong question. In any kind of labour dispute, the question is less about "how do I ask for a better situation?" and more about "what are my other options?". Let's say, you can continue working at this company, getting half pay, working 24/7 on-call hours, and going into personal debt to keep your family afloat, or you can go to another company, work standard 9-5, and get full pay; what would you do? The answer is obvious, you say "hasta la vista" to your current company and move on. On the other hand, what if you have the choice between staying at this company and whatever the situation is, or you can quit and now you have no income at all; what would you do then? Well then we have a more interesting question.
This is really the situation you are in. Your employer is not breaking any laws (unless they are and you haven't said anything). Therefore you have no grounds to sue them or bring a legal case against them, e.g. for lost wages or something else. So your choices are really "take what you can get", or "don't". What does "don't" look like? Is that option better than what you have, or isn't it? If it is better, then you should start looking for a new job, one that you can support your family. If it's not better, well then you don't have too many options...