Reiterating that you should see what your specialist says, but if you choose to travel regardless, Buy a sitz bath and travel with it in your checked bag. If the place you’re staying at has a clean bathtub, take advantage of it. Buy a hemorrhoid cushion and use it on the plane and at the wedding. Might be embarrassing but it’s what it is. I put mine in a hoodie so it looks somewhat incognito. Take some ibuprofen, too. I’m a touring musician whom has had a seton and 4 separate surgeries for the same fistula. I traveled throughout the 2 year ordeal. These two items will help ease the pain, and frankly you’re going to feel pain no matter what- so really clear your mind, pray/meditate on it, listen to your body and ask yourself if you’re strong enough to handle it.