Hi Melaine,
Every single recipe I have for stuffed french toast is done in skillet or on grill...how about preparing them and keeping them in a warm oven around 200-250 degrees until ready to serve? You might lose a bit of crispiness...but I bet it will still be delicious and you will be enjoying the festivities! I would suggest making them as close to possible to eating time of course...but I'll bet they'll do fine! I often keep french toast, pancakes, etc. in a warm oven while I'm preparing breakfasts for large amount of people...Just keep it covered and not too hot! Best of Luck to you!!!
What do the rest of you think??