Whilst there are two marriages of Wilkins/Hall in Birmingham 1934/1935, the marriage of George Wilkins & Doris A Hall, registered in Brimingham in the last quarter of 1934 seems the most likely.
The other was of a Raymond H Wilkins & Eileen M Hall in the last quarter of 1935.
Only the birth certificate, which you can purchase, for Michael P Wilkins, naming both his parents will be the final evidence.