1st Lt. Mark Lee Robb USAAF

Hello Gents:
I am searching for information regarding the death of 1st Lt. Mark Lee Robb USAAF, Service# 0-745182, Serial# 13059918, DOB: 1916, Enlistment Date: 3/29/42, Status: listed as FOD(finding of death??). These are the things we know about Lt. Robb; the following are unsubstantiated things we have heard: Date of Death: 23 January 1945??, Member of 9th Air Force??, B-26 or A-26 pilot??, Died in Belgium??, May have died at the hands of a civilian on the ground??
This information was forwarded to Washinton D.C. and they have hit a brick wall. They wonder if the date of death, or even the place of death is accurate. My brother is taking Lt. Robb's son to Europe soon and would like to take him as close to the shoot-down site as possible. We are asking for TOCH's help. Any information will be greatly appreciated. Thank you and best wishes.