Regarding How to Show Extra paid TDS Utilised .

Very simple.

Split one of the purchase/payment entries of Q3 into two, where the expense of the first split matches the 300 rupees TDS. The second split will be for the remaining amount of the expense.

In your return, enter the Q1 challan for the split and the Q3 challan for the remainder.

(I've been doing something similar for years. I pay a round figure as TDS every now and then and just use the available balance for the return).