How to save on capital tax gain for my father

I have sold a flat for Rs 69 Lakhs on April 2016 which was jointly owned along with my father. The flat was purchased in year 2002 for total Rs 8 Lakhs. As per the inflation index calculation there is total capital tax gain of Rs @ 49 Lakhs . The buyer of the flat has deducted Rs 34,500 TDS each from my fathers and my account (as Total TDS was @ 69000 Rs,).

Now I have purchased new flat in joint name with my wife (father name is not included) for total value of Rs 1 Cr on Sep 2017 . I have paid Rs. 60 Lakhs through a single check to builder from the same bank account where I have deposited rs 69 Lakhs received from earlier flat sale. That means I have utilized all my total capital gain of Rs 50 lakhs in this flat purchase .Currently I have two flats, one in jointly owned along with my mother’s name. And another one along with my wife’s name.

So now my questions is,  as my father’s name is not included in new flat purchase deed how we can claim for share of TDS ( rs 34,500 )which was paid earlier in fathers name . Also  my father do not want to pay for 20 % tax on his share of rs 24.5 lakhs ( total capital gain 49 Lakhs divide by 2) Will this be allowed by tax authority  . He is ready to sign any document saying that he has no objection to invest all money got from earlier flat sale without his name.

So to save my father, for not paying 20 % capital tax gain for his share what options do we have.

Option 1- We claim that I have invested full money of capital gain in new flat(which is true can be shown)  with my father’s consent without his name.

Option 2- Or it is better to buy new property say worth 30 Lakhs in only my father’s name. So it can be shown that his share of @ 24.5 lahs in also invested independently in new flat sale. We do not prefer option 2. But in case option 1 does not work then only we will go for option 2.

Option 3- I have also have flat jointly owned with my mother’s name. This flat was purchased for Rs 22 lakhs in 2011 . Now mother is expired. Can I show that I want to transfer my 50 % share of this flat to my father’s name  to sum of say Rs  25 Lakhs . So in this case, it can be shown that my father has purchased this flat from me at Rs 25 lakhs. So he also save on capital tax gain .

 . Please advise how shall I go about if I want to save my father for not paying capital tax gain.