There could be some wording I'm overlooking but did glean he had limb(s) pain.
For the Casebook entry when he was first admitted to the workhouse, on 18 November 1903, I agree it says
(Pain in limbs).
It's an overflow from the column headed
Work certified by doctor, which reads
Oakum at present (i.e. he was picking oakum, a standard workhouse task -- see
http://www.workhouses.org.uk/life/work.shtml), initialled
H. W. W. (presumably the medical officer). Because he had pains in his limbs he was temporarily being allowed to pick oakum rather than doing heavier manual work, such as stone-breaking.
Then in pencil is written
Pewsey?, querying the poor-law union to which he was thought chargeable (Enford came under Pewsey). He may have been physically removed to Pewsey, but at this date it's more likely that Westminster would simply have billed Pewsey for the costs of his care.
When he was admitted to the workhouse for the second time, on 28 March 1904, he was passed to the infirmary the same day.
There are no admission/discharge records for the Fulham Road
infirmary at this date, as has been stated above (reply #8), so there's no point looking for them at the record office. I believe all the Fulham Road
workhouse admission/discharge registers are online up to 1923. There doesn't seem to be another admission for him, and there are no death-index entries in his name in any Westminster registration district. So he seems to have died elsewhere, and Westminster poor-law records are therefore unlikely to help with finding his death.
When searching the deaths index you might want to be flexible about dates. Although he can't be found in 1911, he need not have died -- lots of people can't be found in one census or another, for all sorts of reasons.
That said, my money would still be on the Nantwich death. But, as I mentioned above, a single man who died away from his family, in an institution, and perhaps with a 'generic' occupation such as Labourer, may be hard to identify from the certificate as your target person. Unless there was an accident and a consequent inquest, you're unlikely to learn anything much beyond the basic cause of death.