Waving to you from the middle of Ontario. There are a lot of Canadians on the forum.
There is no dry food low enough in carbs available in Canada.
Regarding the Royal Canin canned, do you mean Purina DM?
The Purina DM Pate cans (6%) is fine but not the Purina Savory Selects (10%).
Save yourself some money and return it to the vet. Just say that Freckles won't eat it and they will give you a refund.
We are fairly data based here. It is so great that you are hometesting. The Spreadsheet instructions are here:
Come over and post in the
Health Forum. We can help keep your Freckles safe. (It may take a bit of time before you can post – something to do with weeding out spammers.)