According to VW, the transmission is sealed for life. I wouldn't want to go much over 50K miles before a fluid change, however. I had an Escape Hybrid that also had a "sealed for life" transmission and I changed the fluid out on that at 50K, too.
If you don't know when it was last serviced, I'd have it done when you next have the chance. I was quoted around $300-$400 USD at an independent shop. Of course, like all newer vehicles, it needs a particular fluid and you can't just refill it with Dexron III like in the "good old days"!
Any competent independent mechanic can do a brake fluid flush. No need for a VW expert for that job.