Looking for a lawyer

Rather than calling a lawyer I would call an “Expert”. They are listed in the yellow pages under this name. You might have to call two or three in order to get one who will deal with your problem. They tend to specialize as “experts” in different fields. They should be able to recommend someone for what you want. The expert of the insurance company represents the insurance company. Get your own expert to represent you. The two experts can then fight it out between them. We had a similar situation with a fire a number of years ago. Once the insurance expert was dealing with our expert he was much more conciliatory. It was not too expensive but ask him in advance about his fees.

Sounds like you had the wrong type of insurance...

Did you have a broker or did you deal direct with the insurer ?
The broker, if any should help you.

Did you have legal assistance coverage in your fire policy ?
This section of the policy should assist you in case the fire insurer refuses to pay.

Experts will be named if the dispute is on the cause of the fire, ... to investigate the situation but not if it is a dispute on what is covered and not covered.

I have been an insurance company director for 30 years and can answer your queries if you give a bit more specifics.

Good luck to you

Do you own or do you rent ?
You may have to deal with 2 insurers depending on the cause of the fire.
Yours if it is a tenant liability for fire or for your content.
The owner of the building or the syndic, if the cause of the fire is external to you.