The disqualifications were done in a tournament run by an organization banned by the Olympics.
Both boxers participated in tournaments run by this organization with no issues for the last several years.
The organization hasn't said why they were disqualified.
The man spouting the 'trans woman' claims is the leader of the organization. He's a friend of Putin and described as a drug trafficker.
The disqualification for Khelif happened after she beat the previously undefeated Russian boxer Amineva 3 days post fight.

Strangely, nobody who's up in arms about the weird claim has looked into who made it, when, the context around it, or an explanation for it. They just ate it up.