GOWER, Tring, circa 1800
Many erroneous family trees arise because someone guesses what they don't know - and someone else takes the guesses and reports them as if they were true. You confidently make some statements such as "The other James Gower was born in 1788" when familysearch simply records he was "of Tring" and was born "About 1788". This means no more than that at sometime in his life his name was associated with Tring and someone guessed his date of birth (and in some cases this could be 20 or more years out). The IGI on familysearch is a record of the religious ordnances of the Church of Latter Day Saints and in their task of retrospectively saving souls such approximation is considered acceptable by them. May I suggest that you read the web page, The Limits of familysearch, and get into the habit of checking the sources of any entries you find in indexes. Apart from checking that the index is correct the sources often contain additional information which can prove essential in sorting out potential uncertainties.
Clearly the sampler is interesting - and the religious text may be a clue as to whether he was linked to one of the many Baptist chapels in the area. If he is the James Gower who married Elizabeth Humphries in 1813 the marriage register will say whether he was living in Tring at the time of the marriage. A check of the National Burial Index (which indexes the Tring Parish Church registers) does not record his burial. A James Gower, son of James and Elizabeth was baptised in Tring in 1813 and the baptismal register should give James senior's occupation, and perhaps an address. If Elizabeth Gower was widowed with a young child did she remarry? (a 37 year old James Gower, and family, lived in Tring at the time of the 1851 census).
I am not certain about being "press ganged" - at least in the terms we think of today, which involved being forcibly taken on board a ship. "Press" originally meant that you had been hired with a bounty - i.e. you agreed to do a job with a payment of money up front. If James Gower joined the Navy (uncommon in this part of Hertfordshire because of its distance from the sea) he probably joined of his own free will and if he died while in the Navy there may be some record - although I have no experience of the relevant records in the Public Records Office at Kew.
James is a common name in the Gower families in Tring (six are listed in the 1851 census) and this means the problems similar to those described in Right Name, Wrong Body? may occur. In this kind of situation it is useful if people with possibly common ancestors work together to reconstruct the related families so that one can be reasonably certain who was who. I note that you have already been in touch with Angela Brown [see GOWER, Tring, 19th century] and I am sure some joint work should prove productive.
If you can add to the information given above tell me.