nice going I absolutely love the german camo you are doing one hell of a job on that

about medichelmets...
apparantly the painting of medical personnel helmets startet in 1943 with the round circle and red cross but there are other variations on this
1 circle, 2 circles, 3 circles, 4 circles, 5 circles
1 rectangle, 2 rectangles, 3, 4 and 5 rectangles
also just a plain red cross and a red cross with a white line around it that could vary from 1 up to 5 crosses
on d-day almost none of the medics going ashore had a their helmets painted with the red cross and circle. most of them were standard OD7 painted or repainted helmets. the army was thinking that german troops would target the red cross markings so they left them off the helmets. they started re-appearing all over the units around end july start of august again when troops noticed that medical personnel wearing markings were less shot at then troops only wearing the brassard because in some situations it could not be seen by enemy troops. this information also came from interrogations of German POW's
also something that was done is that a second brassard/armband was placed under the netting of the helmet to signify the person as a medic without having to paint his helmet.
about the use of brassard/armbands and the big throwover type thingie with the red cross
standard issue was 1 brassard/armband worn on the left arm beneath the divisional patch.
later on in the war they started to use the throwover thingie and it was more commonly used in rear areas or by stretcher bearers. Rules did not change on the wearing of the brassard and it still stated one should be worn on duty by medical personnel at all times on the left arm... the 2nd brassard was an extra one to signify to enemy troops that the person was a medic and therefore a non combatant and they shouldn't shoot at them because sometimes the left brassard was not seen.
apparently the medic isn't carrying his standard regulation equipment that being 2 medicbags and a medicyoke as a mere private or pfc, 1bag as an NCO and 1 bag as an officer. it appears to me as he is equipped with only a musettebag.
So it could be that he is helping out the medical personnel
sorry bout the long post but i'm a re-enactor and portray a combat medic and am working on collecting myself an aid station so had to stick my nose in it

about the airbornes I guess they are wearing their M43 jumpsuits and not the M42's who were most of them od3 or khaki as you guys say

the M43's were all the same color and that is olive drab green (OD7)
and also the US soldiers are wearing green webbing so it must be later in the war and not a D-day bunch
but market garden and later on