Egypt's forensics authority announced on Monday that the seven men arrested for "debauchery" were physically inspected and were found to be "not gay".
The seven suspects were arrested and accused of debauchery after an online video emerged of an alleged same-sex wedding on a Nile party boat.
"According to inspection, the seven suspects have never had sex with other men," Hisham Abdel-Hamid, spokesman for the forensic authority, said to the media on Monday.
Abdel-Hamid also said that the eighth suspect, who played the role of the groom in the alleged video, didn't show up for the physical inspection.
Prosecutor-General Hisham Barakat ordered suspects to be detained for four days pending investigations into them broadcasting footage that "violates public decency."
Barakat also issued an arrest warrant for two other suspects in the video, which dates back to April, according a statement from the prosecution.
Human rights lawyer Malek Adly denounced the prosecution's order to physically inspect the suspects as a violation of privacy and human rights.
"Homosexuality is not explicitly incriminating in Egyptian law but the government uses other laws instead," Adly told Ahram Online.
In Egypt, consensual same-sex relations are not explicitly prohibited, but other laws have been used to imprison gay men in recent years, including "debauchery" or "shameless public acts."