Suggest you re visit regimental history.
Out of the six existing Punjab regiments, the 1st Punjab, 8th Punjab Regiment, 14th Punjab, 15th Punjab Regiment and 16th Punjab were allotted to the Pakistan Army and
2nd Punjab Regiment to the
Indian Army.
The Punjab Regiment in its present form was formed in 1956 when four of the five Punjab Regiments allocated to Pakistan were merged.
The Jat regiment remained in the IA , the badge shown on the grave stone is the same - only the crown has been replaced by the Ashoka lion