I don't think there is any point to doing HIIT after a weight training session. The weight training does the same thing as HIIT, so it should be better to just follow it with moderate cardio.

You should be eating your fruit and kicking yourself out of ketosis right before your depletion workout. This makes you use more of the glycogen in your muscles in your workout instead of burning fat for energy. This is turn depletes you more thoroughly so that you will be set up for your muscles to better "super compensate" with more glycogen storage (the whole point of the carb-up).

As I said HIIT would be better off done tue. and thur. because that will raise your metabolism all day, which weightlifting is already going to do for you M/W/F.
Sunday you should actually lower your protein and raise your fat, as this will help speed you back into ketosis. Also the best thing as far as training goes to speed your way back to ketosis (Sun) is long, slow to moderate cardio, say just walking or slow jog for 45 min to 1hr 45min.

One last thing, don't be scared to eat enough carbs in the form of fiberous vegies, it will help you GO, if you know what I mean. Eating nothing but meat and fat can stop you up and is no fun. I personally had probs and physlium only helped a little. But then started eating a small salad with almost EVERY meal, even if just lettuce, but often brocolli or cauliflower or stuff like that and NEVER have the problems during keto any more. Carb-ups can be tough in that regard also (digestive issues), but you'll find that out soon enough.

Good luck, hang tough, Chip