The phrase "are only told of" is correct and usable in written English.
It can be used when indicating that someone is informed about something without experiencing it directly.
Example: "The legends of the ancient city are only told of in stories passed down through generations."
Alternatives: "are merely informed about" or "are just made aware of".
"Typically, these workers are only told of the dose they get from an individual or daily exposure, not the cumulative dose over the time they work at a particular plant," said Shrader-Frechette. "As they move from job to job, nobody is asking questions about their repeated high doses at different sites.
In real-life healthcare situations, patients are only told of treatments that their healthcare provider can provide with certainty, and they are not told that the treatment they receive will be decided by chance.
Young said he was only told of it after Hodgson's conviction was quashed.
Wang said he was only told of the reports several minutes beforehand.
It is said Wise was only told of the Shearer development while at a game on Tuesday night.
In this case, Oliver said, the CNS was not notified of Maher's arrest, and the Aboriginal Legal Service was only told of her death on 12 August.
The cabinet were only told of the decision to buy the original Trident C-4 system when the details of the secret deal with Jimmy Carter leaked out in the US.
Natasha's father - though she was only told of his existence when she was 12 - was Edwin Evans, a music critic, friend of Stravinsky and Debussy, who happened to be married.
The prime minister's spokesman said the UK would have preferred to have been informed of the attack and was only told of the Algerian move when Cameron rang the Algerian prime minister.
The OSCE monitors are fully at the mercy of the rebels, and were only told of the fate of the bodies on Sunday: "We are waiting for the rebels to call us and tell us what we can do," one had said over breakfast in a Donetsk hotel earlier in the day.
I think it was the third person afterwards who told me she had had a cardiac arrest". The Whites say they were only told of the reason for Anna's injuries after she had been in hospital for over five months.
