Thank you for the update, sorry to hear there was no additional information to help you. It is very common for family information to become misconstrued. As for your latest candidate, Charles Fullerton, it transpires that may also become challenging.
Private Charles Fuller - not Fullerton, served under the regimental number 1816 - 51st regiment of foot, attached to the 8th Brigade. Alas, no concrete evidence that the 51st were stationed at Quetta. They were certainly active in India during the time period of Private C Fuller, especially during 1878. The regiment was deployed to Afghanistan in autumn 1878 and fought in the Second Anglo-Afghan War, including the Battle of Ali Masjid in November 1878. However, your man Fuller / Fullerton was shipped out on HMS Malabar a year later in 1879 where the regiment was ordered up for active service again when hostilities renewed in the autumn of that year. As you previously mentioned, the Anglo Boer War connection is unfortunately again very tenuous. We have certainly covered quite a few regiments and Fullertons but still no closer to a definitive answer to your quest. I have also revisited the medal rolls pertaining to the 51st Regiment regarding the Boer War as they were then called the King's Own Light Infantry Regiment. No Fullertons or C Fuller mentioned but there was a J Fuller recorded. Evelyn's marriage certificate records Charles, it maybe the soldier in the 51st. However,proving it in my humble opinion has just become even more difficult.
Regards
Dave
You only live once, but if you do it right, once is enough.
Best regards,
Dave