Hello again Tiffany and thanks for waiting.
Sorry to hear about Taji's problems, however I have worked out an answer for you, please read it through and see what you think ...
1. Well you might want to try the Metronidazole if it worked last time and I will give you a link below for the dose rates and contraindications and further information on this drug but before you do this you may want to try a more simple common sense approach. The thinking here is to give Taji's intestinal tract a complete rest and then bring it gradually back to function. I have often advised my clients at my clinic to do the following :
A. Starve him for 24 hours but make sure he has access to water.
B. The next day feed him four or five small light meals in the day. These meals should be the likes of chicken, fish, scrambled egg etc.
C. If he picks up on this diet gradually reintroduce his normal diet over the next few days. You may want to try an option other than the wellness Kitten food in case this was responsible.
4. Live yogurt added to the food can often help. Some gastro-enteritis situations are caused by an imbalance in the bacteria in your cat's gut. Live yogurt is full of " good " bacteria and will seed them into your cat's intestinal tract and restore the balance. You do not need to give much, perhaps a couple of teaspoons twice a day.
5. You can reference this website for further information on Metronidazole. : LINK
Of course if any of the above does not quickly start work or if Taji deteriorates further in any way you should have him checked your vet without delay just to be on the safe side.
I hope I have covered your question fully enough but if you would like further clarification or to talk things over a bit more then I will be on-line for the next hour or so and I will be more than pleased to continue working with you.