Your 22-year-old diagnosis probably doesn't register with your current insurance company. So, they want your primary MD to refer you, I'm sure. Do you have records from that previous UCLA doctor?
Since I don't know anything about how your health insurance works, I can't really say much about it. You might want to call the help line for your insurance and explain your situations. Maybe you already have. But, odds are that you'll need to see your primary physician, who will listen to you about your diagnosis, and probably do the referral without much ado.
What I described is why they do that system for people as a general rule. Your case is your case. But, in most cases, they want you to see a primary care physician to see what that doctor says. You might be able to bypass that, but I doubt it. Fees paid to primary care docs are lower than specialist billings, which is why they do it. With new diagnoses, the primary care doctor can often initiate a care strategy. Then, the referral comes if that doesn't handle it in typical situations. In your case, the primary care person will probably just make the referral, since you have that diagnosis already. The insurance company might try to get the records from the UCLA doctor, though, just to verify.
Although it sounds irrational to you, that's probably how it will get handled. All medical insurance systems have set policies for such things.