Another twin Mum saying don't do it!!!!!
The 3.5 drive will be a nightmare
At that stage I was basically breastfeeding my babies for 8 hours a day. You'd need to be very comfortable feeding in public (which I was later but not at 5 weeks)
Due to the feeding it will be pretty difficult for you even to sit at the table through a meal of several courses.
At 5 weeks I was still very sore post section - I couldn't have managed 3.5 hours in the car.
The likelihood is that you will miss the ceremony as at least one of the babies will be either crying/filling its nappy/throwing up.
At 5 weeks old we had at least one of our babies crying all night. The idea of managing that in a hotel is horrific. Also pretty inconsiderate to other guests.
Twin babies will pretty conclusively steal the bride's thunder. Her wedding day probably shouldn't be all about your babies.
If your DH goes alone (and he'll be shattered for a 4 hour drive but might enjoy 2 nights rest) you'll need someone to move in with you. It needs to be someone useful. You won't need help with the babies but you will need help with laundry/housework/shopping/driving
If you have a section you won't be driving at 6 weeks - your DH does realise that? You won't be able to share driving.
When my children were 4 weeks old we drive to my Mum's house, one hour away, to have a celebration family dinner (not for the babies, for something else) We stayed all day, smiling and nodding - and absolutely miserable. I look back 8 years on and regret we put ourselves through that.
My DH had to go away for work when the babies were 5 months old. He was really, really upset to be leaving me and them for 3 days. Your DH might not find it that easy to leave you for the wedding either.
Don't do it. The very idea is madness.