Sorry, yet again, you're wrong, as you were on growth figures recently.
Reporting to the volunteers in the polling station is NOT the same as reporting to the authorities.
He can report without making public comment.
I quote:
The officer responsible for running the by-election rejected the claims, saying no reports of family voting had been made by polling station staff
A spokesperson for the acting returning officer said: "Polling station staff are trained to look out for any evidence of undue influence on voters.
"No such issues have been reported today.
"If Democracy Volunteers were so concerned about alleged issues they could and should have raised them with us during polling hours so that immediate action could be taken.
"We have operated a central by-election hub which has been rapidly responding to reported issues during the day, in liaison with the police - who had a presence at every polling station - where necessary.
"It is extremely disappointing that Democracy Volunteers have waited until after polls have closed to make such claims."
A spokesperson for the Electoral Commission, which oversees elections in the UK, said: "We are aware of the report. Electoral offences are a matter for the police. We encourage anyone who believes an offence has occurred to report it to the police.
"The statutory electoral observer Code of Practice says that electoral observers may bring potential irregularities, fraud or significant problems to the attention of elected officials on the spot"
Looks very much like they have an axe to grind or don't know the very rules they (unofficially) seek to uphole.