The 23-year-old took Airdriedonians FC and one of its directors, Paul Hetherington, to an employment tribunal over allegations of racial discrimination.
He claimed he was racially abused by a fan during a game last year, and while the club carried out an investigation into the matter it was later dropped due to “insufficient evidence”.
An employment tribunal hearing in Glasgow examined how the case was handled, with Quitongo claiming he was a victim of racial harassment and victimisation.
However in his ruling published this week, tribunal judge David Hoey said the claims were “ill-founded” and ruled against Quitongo.
Commenting after the ruling, Quitongo said: “This judgment is a bitter blow for everyone who has stood up to racism in our national sport.
“This entire episode has been an incredibly distressing, traumatic, and harrowing experience for my family and friends, as well as myself.
“I have been inundated by a groundswell of support from football fans and players alike during this lengthy and arduous legal process. I am hugely grateful for this solidarity.”
In his witness statement to the hearing in June, Quitongo said he was told on the evening of Saturday September 11 last year that someone had overheard an Airdrie fan racially abusing him at the game that day.
He said he felt “upset and disgusted” after listening to a voice message telling him about the racist slur, and the following day he reported the incident to the club.
The employment judge said the club and Mr Hetherington – referred to as the respondents – could not be held responsible for the alleged abuse as it was said by a supporter and not an employee or someone for whom either respondent was, in law, responsible.
The ruling said: “The allegation was that a spectator had directed racial abuse towards the claimant. This is not an act for which the respondent could be liable in law under the Equality Act.”
Quitong left Airdrie in January this year to move to Peterhead FC, and he now plays for Queen of the South.
Quitongo had backing from the Equality and Human Rights Commission and the Professional Footballers’ Association (PFA) Scotland union.