Can I use ceramic crock pot liner in 350* oven

Most of the removable crockpot inserts can be used in an oven. The upper temperature limit varies by the manufacturer though, and you would want to check with whoever made yours. If it is a name brand Crockpot, the insert is safe up to 400F. I know this because I own one of these, and that's what the package insert says, as well as their site. You just want to inspect it closely for any hairline cracks first, and keep in mind it will be subject to thermal shock just like any other ceramic or glass baking dish. It will need to go in the oven at room temp or higher, and be careful not to put it directly on a cold surface when you take it out. I also don't use the glass lid that came with it, and opt to use a foil cover instead. I've also used a pie plate on top as well. Since your recipe starts with a cold oven, you should not have any problems with thermal shock going in.