post a photo of the crease.
When the quilts are dented or creased, you can't fluff it up or fix it. One of my jumbos has two deflated quilts on the back bottom corners (purchased straight from chanel store back in 2012. It was my second purchase)..i regret not exchanging it to this day but I'm thankful it's only on the back. Front creases even if it's covered by the flap would be a deal breaker for me because I'm assuming when you open it, you can see it.
Don't settle.
5k is alot to spend on a purse that it not fixable or obvious (like in the front).
Good luck on your first purse. Make sure you have no doubts. I buy from store and preloved and what I've learned is that if you have any reservations (to the point where you're posting on here asking us) , you probably shouldn't get it. If you love it, you'd jump on it with fear it would be gone if you didn't.