You might want to contact Fortress Louisbourg National Historic Site regarding burial.
He must have died of sickness as the siege was in July 1745. He probably subsequently joined Shirley's or Pepperrell's regiments that were raised from the other New England units that were being disbanded after the campaign. Shirley's or Pepperrell's regiments were raised to garrison the fortress, with some British units, after its surrender. They were disbanded following the end of hostilities in 1748.
To Join the Company of Military Historians click here