Dad has lung cancer, neck, throat

My father was just diagnosed with lung cancer with spreading to the neck and throat.  He is not a surgical candidate because of his emphysema, COPD, chain smoking, diabetes, strokes, etc., etc.  He is also deaf and doesn't understand what is going on because he can't hear what is being said about his health.  My mother writes him notes and makes his decisions for him.  She communicates only what she wants to.  The doctor suggested another biopsy (he had a lung biopsy) and mom or dad doesn't know why. They did not ask for records or get ALL the information needed before making a decision to get chemo. He has squamous cell carcinoma and a total of 4 lesions/tumors in left and right lobe, parotid gland, and lymph node/throat???? Not sure what all facts the nurse told me about his PET scan and biopsy. Dad thinks the chemo will cure him after a few days of getting sick. The doctor said it would be the cruelest thing mom could do if she did not get him treatment so they decided to go for it.  We are all for treatment to save him, but not without anyone getting the facts first.  My mom has told all four of us kids that we cannot come over or help in anyway because we questioned her and disagreed with their decision (when she said at the beginning she would include us all in the decision making process) but apparently changed her mind. I don't want to tell my dad the bad things about chemo and that it will make him very ill and he could die anyway.  I feel they are all rushing into chemo treatment without full knowledge of the side effects.  He is 78 years old and is in the worst health and so is my mom.  Does it sound like chemo alone would help my dad?  They said at the last biopsy that his lung could collapse and if he went on a ventilator he would not come off of it because the last time he almost died.  Another biopsy (I think the nurse told me it was the parotid this time).  What are the recovery and risks after this biopsy? He has also had numerous strokes and has 100% blockage on the left carotid and had 95% blockage on the right. After they did surgery only on the right, I am not sure what percent he has now but it is not fully 100%. I can't call my dad and talk to him and have no other way to communicate unless I go through my mother and she does not want us to come by or call or help. How in the world is she going to take care of my dad?  Does he have a chance of survival?  It sounds like stage IV to me but mom does not want to "inconvenience" the doctors to ask questions or get records for my dad to read.  I am afraid that he has no clue what he is saying yes to and does not have all the information he needs.  I know it is hard to say no to treatment and give up but I don't think he will make it after the first round of chemo. I am troubled and don't know what to do for my dad.  This is terrible. He has been told that all of his kids are against him getting treatment without knowing why we said that.  I am between a rock and a hard place.  It is my mom's decision but I don't think she has my dad's best interest at heart. My dad continues to chain smoke and said he will continue to smoke even after he is "cured".  Help please?  I am ready to just sit and home and cry and pray for my dad and hope everything works out.  I would love to hear your opinion as this is hurting me tremendously.