They are investigating the cause, and you are in it
When a building insurer pays an owner, it frequently looks at whether a tenant caused the loss, because if so it can seek recovery. A friendly call asking what happened is part of that process. It is not hostile and it is not neutral, and the answers go into a file that may be used against you.
Tell your own insurer before you tell theirs
If you carry renters insurance, report it to your own carrier first and let them handle the contact. That is what the liability section is for: your insurer deals with their insurer, and you stop being the person answering questions alone.
A recorded statement is a decision, not a formality
You are generally not obliged to give one to the other side’s insurer, whatever the tone of the request. It is reasonable to say you will respond through your own carrier. Tenants without cover have nobody to route it through, which is the real cost of going uninsured.