Henry Marshall is listed in LDS microfilm 1130493 as being a British subject in Samoa. He was born in Stepney(London, England)and was a carpenter aged 61, living in ?Tausimafa? in June 1878
He is NOT listed as being a British subject in 1881, when the british Consul in Samoa conducted a Census of British residents to match the 1881 British Census, which presumably means he was dead by then.
James Laurenson is listed in 1881, aged between 40 and 45. He was also a Special Constable in 1876, to support the Constitution and the laws on Great Britain
There may be other mentions of both of them on this microfilm, and on microfilm 1130492- the British Consular records.