Stephen Packer said the proposal document to drop the National Screening Unit contract lacked specifics, and it was difficult to get straight answers from managers, who were acting ''like politicians''.
The Public Service Association yesterday labelled the consultation a ''sham'', and the senior doctors' union is also not happy about the situation.
Mr Packer was a semiretired breast surgeon who agreed in April last year to assist BreastScreen Healthcare when the Ministry of Health said it needed more support.
He also has an informal role supporting the diagnostic breast-care service, the future of which is now uncertain - it is outside the scope of the screening contract the board is considering relinquishing, but works closely with that service.
He feared for the viability of the diagnostic service on its own, and there was not enough time to investigate the situation in the two-week feedback period.
Due to the service's shortage of radiologists and its vulnerability as a small service, the board is considering opting out of the contract, which ends on June 30 next year.
The service relies on support from Counties Manukau DHB, which has given notice it is ending the service in the middle of next year.
Staff were told on Monday and have two weeks to give feedback.
Mr Packer was told before staff, on Friday, but would have preferred an opportunity to have input much earlier.
The diagnostic service, for women who have symptoms, was closely linked with the screening programme, yet the board had only said further investigation was needed in to how the diagnostic service would cope if screening was performed by an external provider.
In a relatively small population area like Otago-Southland, a strong link between diagnostic and screening was more important than in larger centres.
''The general feeling among staff is that the decision is likely to have been made; that this process is simply one to cover the employment requirements,'' Mr Packer said.
He would like to see the service kept in-house, supported by a long-term arrangement with another provider, perhaps in a regional collaboration.
It was vital the health board recognised the value of the screening service, and the knock-on effects of losing it.
Recruitment was a challenge, as breast radiology was not ''particularly glamorous'', but it was not good enough to say: ''[It's] too hard for us. Somebody else can do it''.
''That really has ... a downgrading effect on the whole hospital community, the medical community, and the community as a whole.''
He likened the situation to the threat over agricultural research centre Invermay, saying too many things were ''being done'' to Dunedin from the outside.
Public Service Association (PSA) southern region organiser Julie Morton labelled the consultation period a sham, as it was too short to address serious issues raised in the proposal.
She said the board should have advised earlier Counties Manukau DHB was withdrawing.
In response, Southern DHB patient services director Lexie O'Shea acknowledged in an email it would have been preferable to have more time to work through the options with staff.
''However, it is only now that we have now got to a point where both the unfilled vacancy remains, and where Counties Manukau have confirmed they can no longer provide the service from July next year.
''We were notified of this by Counties Manukau in July and have since then been in talks with them and with BreastScreen Aotearoa.''
It was unclear why the 1.3 full-time equivalent radiology vacancy had been difficult to fill, she indicated.
Association of Salaried Medical Specialists executive director Ian Powell said the board needed to improve its planning and recruitment processes to ensure it had enough specialists for vulnerable services.
He questioned why a regional collaboration model was not considered, given health boards were supposed to work together.
''Is some of this regional collaboration talk just rhetoric?''
