Do My Sue my ex-employer insurance carrier my ex employer for unfair dismissal ?

Do I Sue My Employer or their Insurance Carrier?
I was injured on my job. I went to the doctor and he prescribed me a treatment that the insurance or the claim adjuster had to approve. I call the claim adjuster, she told me she doesn't think it would be necessary to have that treatment, and told me I would have to meet their nurse at the doctor's office.
I wait for 5 weeks, they never sent me any note approving the treatment. Frustrated, I called the workerboard compensation, and explain the situation, when that person called the insurance carrier, that person was told, the treatment was approved. I was a lie.
I have proof from the doctor, that he never received any approval. In the mid time because I could not provide any doctor's note to my employer, I got fired. Do I sue the employer insurance carrier?
1 second ago - 3 days left to answer.

Depends where you are.

First off, if you're in the US then, in most States, it's perfectly legal for your employer to fire you for not coming to work if you're unfit to do so.

Second, the absence of a doctors note saying you were unfit to go to work was not related to the insurance company not approving the treatment. If you weren't fit to work then your doctor could have given you a note saying so - he could have said on the note that you were not getting treatment because it wasn't yet approved by the insurer if he chose, but that didn't make any difference.

Firing you was a dumb move on the companies part (Since you were off work on workers comp you'll continue to draw workers comp at their expense until you are released as fit to look for the same line of work by your doctor. If they'd been willing to bring you back in on restricted duties that your doctor said you could do, they'd have saved themselves a lot of money) but it wasn't illegal in the US - in your country may be different.

Richard