One week out is the paperwork cross-check: confirm the microchip number matches exactly across the pet passport or health certificate, the vaccination record, and any permit paperwork. A mismatch is one of the more common, entirely avoidable reasons pets get held up at a border.
Pack any regular medication in its original packaging along with a letter from your vet confirming what it is, the dosage, and that it's for your named pet — this resolves most questions at a border check without further discussion. Pack enough to cover the trip comfortably plus a few extra days.
If your dog needed a category 2 permis de détention, confirm it's actually been issued and that you have it, along with the civil liability insurance certificate, ready to produce if asked — not still in process. For a category 1 dog, this is the point to have already confirmed, with certainty, that the trip isn't legally possible, rather than discovering it this late.