• Income tax notice U/S 142(1) and don't have proof of certain deductions

I received IT notice U/S i42(1) & IT department is asking to furnish complete documentary evidences. I have around 6 bank accounts, however use actively only 3. One of them have been inoperative with 10K balance and for other 2 I lost the user id, account numbers and passwords as I never use them. IT department is now asking to furnish statements of all bank accounts (whether closed) maintained during the year under consideration with narration of debit & credit entries.

Questions
1) Is there anyway where I can avoid the bank account statements because IT department already has my bank account numbers. Can I submit the account numbers and bank details. For the 3 active accounts I can submit the statements. But for inoperative accounts it is very difficult as i moved to another city. However balance is very less there (~10K) and no debit/credit happened in that FY. Practically what is the way to avoid doing so much work and submit just the account numbers which the IT department can easily verify.
2) I claimed 1 lac deduction US 80DDB and this was because one of my parent was suffering from dementia and parkinsons and was fully bedridden. I had to buy a wheelchair & anti bedsore mattress. I have medical records, prescriptions, discharge summaries and death certificate. Can I submit those to prove and request AO to consider medical evidences. Trying to get a statutory certificate was practically impossible during that stressful time as she was fully handicapped and dependent on us. Can AO reject due to lack of prescribed certificate which is a technical issue. The deduction was genuine. 
3) In my earlier city I had a home loan. However the possession was given after the FY (i.e. after 31-Mar). So I stayed in rented house for that FY and claimed both HRA, Home loan principal deduction under 80C and Home loan interest deduction. My office finance team allowed it when I enquired from them at that time. Please confirm this is correct. If not please provide approach to get it allowed.
4) Is there any immunity option available ? I lost a close dependent family member last year who was suffering from dementia and parkinsons. So there was lot of expenses and I took lot of leaves. So a high penalty and fine will not only be financially oppressive but will cause irreversible financial prejudice. 
5) If I submit a deduction receipt (without bank account statement/details) & it gets rejected by AO then is there any consequences other than fine/penalty ? I have one deduction without receipt. 
6) Please share some good judgements applicable to my situation. Due to financial crunch some deductions were claimed last year.
7) IT department has asked to furnish copy of computation of income for the year under consideration along with supporting documents. Where can I get the computation from efiling portal (https://eportal.incometax.gov.in/). I downloaded the JSON file and PDF file. Is that the computation sheet? Earlier city tax guy is not available now