He's British and he's James Edward Rose and obtaining his service record isn't a problem and you don't need to supply any proof of death, because he died whilst in service, it costs £30.
https://www.gov.uk/requests-for-personal-data-and-service-re...The death certificate isn't a problem if you want a copy, and it costs about £10.
http://www.gro.gov.uk/gro/content/UK GRO...War deaths, Army, other ranks 1939-1948 Rose James E. Rank = Sgt. service number 4911764 unit = A.A.C. year of death = 1944 Volume 16 Page 95.
However, before you get into that, you need to sort out who the correct man is, because there's a big mix up going on here somewhere, because you've got an enlistment document for a man who enlisted in the Devonshire Regiment around 1929 or 1930 and who claimed to be 18 but who was really more like 16 and who claimed to have been born in Darlaston in the Walsall area of County Staffordshire in 1911 but who was really born there in 1913, that is if he didn't also spoof his place of birth.
He enlisted to serve for 9 years with the Colours and 3 years in the reserves.
You also have a notification document about his death in June 1944, or at least about the death of a family member of the same name.
That lists him as Serjeant J.E. Rose 4911764 Army Air Corps, aka the AAC,...his Commonwealth War Graves Commission aka CWGC record lists his unit as 9th Battalion the Parachute Regiment AAC,...that battalion was created in late 1942 from 10th Battalion the Essex Regiment., I wonder if they had a choice in the matter. ! Of course he could have later volunteered or been transferred into 9th Para.
However, in the case of the 1944 man above, and for whom you have the death notification document, which presumably was and is a family possession, both his CWGC record and his headstone list his age as 21, so he was born circa 1923, and there is one birth record which matches a 1923 birth, in County Middlesex, his mother's maiden surname was Gurry, the maiden surname of the mother of the 1911/1913 Staffordshire man was Clark, which matches your records.
You have his father dieing in 1916 and you have his mother listed as Catherine Rose nee Clark, and you have her remarrying in 1955 aged about 65 to Thomas Arkinstall and dieing in Walsall in 1974.
However, your 1944 death notification document was addressed to Mrs. C. Wheeler.
The 1955 marriage was between Thomas Arkinstall and Charlotte. Wheeler
So either his first period of service ended before the war, and he had been in some sort of trouble in the army and had enlisted during the war and had understated his age by 10 to 12 years.
Or the CWGC have made a massive error in his age, which is unlikely,but possible.
Or else you have made an error, and whoever obtained his service record from wherever, may have got the service record for a different man, but it seems that you didn't get it, or at least the first page of it, which you already have, from the MOD.
So where did you get it from. ? If it was obtained from another family member who had got it previously from the MOD it should have the rest of his record as well, but presumably that might have been lost, and if they did get that record from the MOD they may have got the record for the wrong person.
There are a few other oddities about this situation, but I won't mention them at present because they won't help to clarify this matter, and they'll just cause more confusion.
The crucial key to sorting this out is his service record, you have only posted the first page of his record, i.e. his enlistment details, and if you had applied for it from the MOD you would have had the rest of his record, which will list his service and his unit or units, and most crucially it will list his service number, and if you had the rest of the record, you could and should post it here as an attachment, but you say that you haven't yet applied for his record from the MOD.
How you managed to post either of your documents is a mystery to me, because neither of them had a filename extension and they wouldn't open offline when I downloaded them, which I did because documents posted on here are very difficult to read, even when they're posted the right way up.
I added a jpg filename extension and they now open OK in an image viewing program.
http://www.cwgc.org/find-war-dead/casualty/2344255/ROSE,%20J...http://image2.findagrave.com/photos/2014/55/56097077_1393366...http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GSln=ro...;