The Springbok group was cut from 32 players to 31 for the upcoming finals and the squad reveal had threatened to be marred by social media allegations of an incident involving the lock.
However, responding to the reports, Etzebeth provided a categorical denial - and the South African Rugby United (SARU) insisted it will stand by its man unless further informed by authorities.
"It is completely untrue and unfounded to claim that I physically or racially abused anyone in Langebaan as has been reported on social media," he posted on Facebook. "Multiple witnesses can corroborate that.
"I am and will always strive to be a true ambassador to this beautiful rainbow nation and the sport that I love."
A SARU statement read: "The South African Rugby Union is a law-abiding member of South African society and has no tolerance of acts of violence or racial abuse.
"We will co-operate with the authorities in any way necessary. Our Rugby World Cup squad will have no place for anyone who transgresses those principles.
"But we also trust our people to act responsibly and tell the truth. We have spoken to Eben and he categorically denies any physical or racial abuse on his part as has been alleged in social media.
"He is a member of the Springbok squad and will remain so unless police authorities require our reconsideration."
Springbok World Cup Squad announced:
— Springboks (@Springboks) August 26, 2019
Erasmus said: "I am very happy with the squad we have been able to select. We have been developing this squad since the start of last season and, in the 31, we have a good balance of established experience and some exciting youth.
"We set out with the goal of growing the depth of the squad and I am confident that any of this 31 can step into a play-off match at the Rugby World Cup and deliver an outstanding performance."
Rugby Championship winners South Africa begin their World Cup campaign against defending champions New Zealand in Pool B on September 21.
South Africa squad in full:
Forwards: Schalk Brits, Lood de Jager, Pieter-Steph du Toit, Eben Etzebeth, Steven Kitshoff, Vincent Koch, Siya Kolisi, Francois Louw, Frans Malherbe, Malcolm Marx, Bongi Mbonambi, Franco Mostert, Tendai Mtawarira, Trevor Nyakane, Kwagga Smith, RG Snyman, Duane Vermeulen.
Backs: Lukhanyo Am, Damian de Allende, Faf de Klerk, Warrick Gelant, Elton Jantjies, Herschel Jantjies, Cheslin Kolbe, Jesse Kriel, Willie le Roux, Makazole Mapimpi, S'bu Nkosi, Handre Pollard, Cobus Reinach, Frans Steyn.
Photo Getty Images. Caption: South Africa lock Eben Etzebeth