Bong was at the centre of allegations of racial abuse made against striker Jay Rodriguez when the sides met in January 2018, with the Brighton defender claiming he said to him "you're black and you stink".
Rodriguez had claimed he told Bong his breath smelled, with Baggies fans directing "smelly b*stard" chants towards the full-back in Wednesday's FA Cup replay.
Indeed, the game was the first meeting between the two sides at the Hawthorns since the incident, which took place during Albion’s 2-0 win over Brighton in the Premier League last season.
Speaking after the game, Brighton manager Chris Hughton called for the relevant authorities to look into the chants and take action: "What we heard tonight is not nice. What we have in Gaetan is a very upright, respectable individual.
"For those who make those chants that’s their individual choice and it’s down to the authorities and governors of the game to deal with. The game in recent years has acted on such things really well.
"All Gaetan wants to do is very much get on with his football. He has conducted himself impeccably."
Just 9,000 fans turned out at the Hawthorns to see Brighton come from behind to ease into the fifth round of the FA Cup.
Championship side Albion had looked set to cause an upset against their Premier League opponents when Kyle Bartley gave them the lead with 13 minutes left to play, but striker Florin Andone sent the game into extra time with an equaliser five minutes later.
By then, the 25-year-old forward should arguably have not been on the pitch after a controversial incident with Albion midfielder Sam Field that saw him seemingly connect with the West Brom player with his elbow.
And Brighton took advantage of their good fortune, Glenn Murray’s two goals in the extra-time period ensuring that Hughton’s side will face Frank Lampard's Derby County in round five on February 16.