It appears that on 19th and 20th Sept 19 Field lost two OP parties in the mountains in support of 66 Brigade. No doubt due to weather but they would most likely to  have been captured wandering into enemy lines. There is an incident in the 67th’s diary where a Captain, Bombadier and muleteer were delivering batteries to an their FOO who was constantly moving with the infantry to maintain contact with the enemy. They stopped to ask for directions from a local farmer. Seven men were seen approaching  so the muleteer and Captain hid in a barn while the Bombardier was speaking to the Italian farmer.                It became obvious that it was a German fighting patrol who asked the way to the German Lines. The farmer was too scared to answer so the Bombardier spoke to them in Italian, sending them in the opposite direction to where he was heading, There was a note in the diary regarding the benefits of non standard dress worn by British troops in the mountains.      You need to get copies of their War Diaries to see if there is more info on this. I have contacted a friend to see if he has anything on it but I am told their War Diaries have very little information just short notes day to day.  There are other sites who can help on this particularly WW2Talk. Having been at Anzio he might have contracted Malaria or Jaundice both very common and causing admission to hospital for quite long periods.