Mike,
I have followed this thread but not contributed because I have no expertise in the field of mental health. Firstly you have the same rights as anybody else to pursue your wishes. As you know there are many pilots that have overcome illness or disability to embark on a sucessful career. For what it may be worth my advice would be to apply for a Class 1 medical certificate. This will cost a few hundred pounds, but failure to obtain it would limit your potential loss to just this sum.
Presumably "panic attacks" are a laymans term for a whole host of conditions that may be temporary or spurious or permanent. It has to be said that whilst you cannot guarantee that any human being is not to going to fail in flight, the purpose of the medical requirements are to minimize the risk as much as is reasonably possible.
Clearly anybody prone to such a condition cannot be considered as suitable to operate in a public transport role. There have been a few high profile cases of pilots being affected by such conditions in flight, and the results have been disturbing and frightening for the other crew. In situations where a crewmember may have suffered a serious trauma or injury, it is not unusual for the CAA to refer the individual to a Psychiatrist for an assesment and report. One of the investigation requirements is to try and ascertain that the individual is not likely to have any latent trauma that might manifest itself under conditions of stress.
There is no simple answer to this. Any answer will ultimately and properly be given by the CAA, but in reality I think you already know that this problem ( or history of such), is going to present a serious obstacle. Despite what you may have been told on the phone, you cannot take that as gospel and would have to be properly assesed.
Employer issues are not likely to be the difficulty, it is the aquisition of the Class 1 medical that is likely to be the problem.
For an employer medical questions are often satisfied by the presentation of a valid medical certificate. Of course if an employer does ask you questions relating to your health or history, it would be incumbent on you to make relevant disclosures.
I know you asked for frank opinions, and I am sorry if this sounds less than encouraging. Nevertheless I think it is realistic and again the first thing you should do is apply for a Class 1 initial medical. If you have doubts about doing this, you have probably answered your own question.
Good luck !