I know that's tough.
They're not bound by the legal rules of evidence. So they can hear people quite informally and expeditiously. That relates to not making it difficult for people to make a claim. So they can relax rules. They're much more relaxed than they would be in a court of law.
However, let's say, for instance, they want some information that is in fact protected by solicitor-client privilege; then it's protected by solicitor-client privilege, but the tribunal can otherwise relax its rules for hearing evidence.