He had apparently come to join Wolf's Dragoons from Clan space, as opposed to being an adopted recruit from the Inner Sphere. This is implied by his knowledge about the Dragoons' Hegira plan even though he was only a regular MechWarrior, whereas recruits from the Inner Sphere were briefed on Hegira only upon attaining the rank of company commander. Further indications are his peculiar attitude towards Jaime Wolf and his references to Wolf's age (unremarkable by Inner Sphere standards, but old by Clan standards), his reference to the Dragoons as the "Wolf Dragoons" as well as Kerensky's reaction to his betrayal that referred to Clan traditions and laws.
According to a ComStar report Fadre Singh only appeared in the Dragoons' roster in 3020, suggesting that he may have been added to the Dragoons in their last supply run to the Clans in 3019 (after their costly attack on Hesperus II).
In 3023 Wolf's Dragoons, then employed by the Draconis Combine, raided the Federated Suns world of Hoff where they met stiff resistance from the elite Eridani Light Horse mercenaries. In one situation, while his commanding officer was still pondering whether or not to commit his unit to a frontal attack, MechWarrior Singh marched off on his own and assumed command of the entire company. They breached the enemy lines and destroyed a vital enemy installation, contributing greatly to the success of the campaign. However the assault led by Singh resulted in the death of a lancemate and the destruction of several Dragoon 'Mechs.
The stunning victory on Hoff and the extensive media coverage precluded a court-martial of Fadre Singh for insubordination for publicity reasons; instead, he was promoted to an "important assignment" on the desolate border world of Misery.
On Misery, Singh met a fellow MechWarrior (a female mercenary implied to have been a ComStar ROM agent) to whom he revealed secret Dragoon information regarding the existence of a Hegira plan, the Dragoon exodus plan from the Combine. The new ComStar Precentor on Galedon V, Alexandre Kalafon, notified Draconis Combine Warlord Grieg Samsonov of Singh's disposition on 2 November 3026.
Tensions between Wolf's Dragoons and their employer, the Draconis Combine, later escalated until a military confrontation was fought on Misery in early 3028. Over the course of the battles, Fadre Singh piloted a Crusader in the Combine's forces and held the rank of Tai-sa (Colonel). He was captured when his 'Mech was downed in an ambush by Dechan Fraser's lance on 23 April 3028, and taken to the Dragoon HQ. When Singh boasted that he had revealed information about the Dragoons' retreat route to Warlord Samsonov, Natasha Kerensky shot him on the spot, with the words "Those who break faith with the unity shall go down into darkness" as smoke rose from the barrel of her Marakov pistol. These words were the same spoken by Nicholas Kerensky when he ordered the Annihilation of Clan Wolverine.
Jaime Wolf later mentioned to Minobu Tetsuhara that Warlord Samsonov's troops had ambushed the retreating Dragoon families in space. Since the Hegira plan called for an escape along a secret route, separated from the main fighting body, this was likely only possible because of Singh's betrayal.
It is notable that Fadre Singh, being himself of Clan origin, could have warned the Inner Sphere about the Clans some 21 years prior to the Clan Invasion. However, he apparently did not divulge information regarding the Clans, probably thinking that it would not be believed. Alternatively it could be speculated that the information was dismissed as unbelievable, or that it was deliberately withheld by Warlord Samsonov and died with him when he was executed shortly afterwards.