Cowen was Frank Cowen. More details on the attack here on page 12 (see March 25th entry). Not sure why the date is different.
It also may be that remains were recovered but could not be identified as Barber post war.
http://www.ex-cbi-roundup.com/docume...0_february.pdf
There is also mention of the attack on this link but search for "Cowan". It describes how both men were taken to a doctor on base. That would suggest possibly that Barber's body was pretty much intact (not burned up for example).
http://www.cbi-history.com/part_vi_1...mando_gp2.html