From what you've written it seems evident that there has been some uncertainty about your father's employment status over the years.
Initially, you referred to him as "self-employed", but have gone on to say that he was "working for the family business" and you later mention that he was "employed there". All of these things have different meanings when it comes to PRSI Classes, so you/he need to establish his exact employment situation for each of the years. It's fair to assume that from his perspective he wouldn't have been aware of the significance of that which is why his professional adviser must be asked to clarify the situation, year by year.
So instead of asking who else can help, you first need to tackle the source of the information that was filed with the Revenue Commissioners and Social Welfare over the past 34 years - and that's the accountant. I appreciate that this may require a difficult conversation - or a solicitor's letter! - but it must be done. Because until that has been clarified, you're not even at the start line so cannot take any steps towards addressing the situation.
Initially, you referred to him as "self-employed", but have gone on to say that he was "working for the family business" and you later mention that he was "employed there". All of these things have different meanings when it comes to PRSI Classes, so you/he need to establish his exact employment situation for each of the years. It's fair to assume that from his perspective he wouldn't have been aware of the significance of that which is why his professional adviser must be asked to clarify the situation, year by year.
So instead of asking who else can help, you first need to tackle the source of the information that was filed with the Revenue Commissioners and Social Welfare over the past 34 years - and that's the accountant. I appreciate that this may require a difficult conversation - or a solicitor's letter! - but it must be done. Because until that has been clarified, you're not even at the start line so cannot take any steps towards addressing the situation.