• Deduction of TDS from rent supposedly given

Kindly advise,taking the following points into consideration.
1.There is a tenant,which is a registered private PARTNERSHIP FIRM,on rent in our house,on a tenancy agreement,that specifies explicitly,that TDS deducted from rent given by tenant would be deposited with IT dept.
2.For the last 6 years,it has not paid us rent,nor has it deposited any TDS deducted from rent with IT dept.
3.It doesnt possess a TAN number.It is a fake private engineering institution with staff,faculty & employees.
4.When I questioned about rent & TDS to the tenant,it did not reply.I then wrote to the IT dept & to the Police to investigate.
5.The IT dept issued notice to tenant,upon which,the tenant gave a FALSE declaration to the IT dept that it is a sole proprietorship/individual & that its account books are not audited & hence provisions of TDS didnt apply to it.
6.I submitted the registration details as a partnership firm to the IT dept.
7.The tenant has unofficially sent some xerox copies of payment of rent received by my Late father(each year the rent paid was 180000 Rs).The signatures appear fake & have not been done on Revenue Stamp & the rent receipt has been written in the tenant's handwriting.My mother however says that no rent was ever paid by the tenant & none of the money seems to have been deposited in any bank account belonging to my mother or my father.Its very likely that the tenant has faked.
8.The IT department has now sent me a notice asking me to produce proof of actual payment of rent & a legal heir certificate,to adjudge whether the provisions of TDS are applicable in this case or not.There are 3 legal heirs,me my mother & my sister.My father expired in Nov 2015 & rent was supposed to be paid from the month of Jan 2011.

Kindly advise on the following-
1.Is giving false declaration to IT dept to escape a TDS fraud an offence or not?
2.Is the concerned ITO trying to save the tenant as it appears to me.
3.Is being a private partnership firm & an engineering educational institution with teaching/non teaching staff & faculty,not enough ground to have provisions of TDS applicable?
4.What should be my reply to the ITO?(The ITO,infact,at the first instance,just accepted the false declaration of the tenant as an individual,never bothered to investigate & closed the case,till I brought the truth to notice,that the tenant is a regd. partnership firm)