Balance:

Question

NH3 + [Cd(NH3)4] > Cd2+ + NH4+

Answer 1

You are missing something.

NH3 + [Cd(NH3)4]²⁺ > Cd²⁺ + NH4⁺

Is that what you mean?

Then it will never balance.
On the left, for every Cd, you have +2 charge. On the right, for every Cd, you have a +2 charge AND a + charge for each N.

Somehow, something has to be reduced for this to happen. Charges just can't be manufactured.

So I guess I don't understand what you mean.