Thank you for this information. I have been searching for his burial place since 2000.
There is one discrepancy though. He actually died in Philadelphia, PA on 3/1/1865 of consumption while on duty with the 7th New Jersey Infantry. I have a sworn affidavit by Dr. Lehlbach who was the Surgeon of the 7th NJ to verify the date of death. Since he was originally buried in Mount Moriah Cemetery in Philadelphia I suspect the date on his tombstone is the date or close to the date that he was re-buried in Rahway Cemetery. Of course the tombstone in Rahway Cemetery may only be a cenotaph and he may still remain in Mount Moriah Cemetery. Further research will need to be done on that aspect.
Since I am not related to any of the families you've mentioned I can't provide anything specific. There are many Brown's in Rahway and the surrounding towns. I do know that there is an Asher Brown (1743 - 1794) buried in the Connecticut Farms Cemetery in Union. Whether he is any relation to your Asher Brown I cannot say.
This is a link to the Brown's in the Connecticut Farms Cemetery: