Kim, did the problem improve?
Our second bengal had TF and gave it to the first one when they were kittens. I had to research this myself. Poop would be OK few days and then go loose again and it would smell like Satan, dead and buried
Apparently this is how it works, runny poop stars when the parasites die and shed and then you get few good days.
The vet was useless and we were in UK at the time so I presume you are in the same boat. They did not have a test for TF so she tested for other stuff and gave us useless antibiotics. I then researched online, found the only lab in UK that does TF testing and had to persuade the vet to try that option. It came back positive. The antibiotic for TF had to be sourced from USA and the vet had to make the pills according to weight of the cat. Pilling was so hard, especially with one of our cats that is not treat driven. But after the treatment they were both fine and now they are 8 years old almost and never had a problem again. TF can be dormant and suddenly activate when the cat is stressed so he may not have had any symptoms before.
Food wise - I found one of my cats reacts to everything but fish seems to be OK. We feed good quality wet food and some dry. In UK I used to feed them Hi Life food and Lilly's organics fish - see links. Lilly has nice wet pate foods too but one of my cats would not have that. Both Hi life and Lilly's I used to buy in Waitrose and Ocado (not sure if you have that in Ireland).
I find that sometimes so called 'good' and 'grain free' food makes my cat worse. They often have no grain but contain stuff that can't be good for cats, such as peas, beans, pea protein, potato starch, chickpeas etc. I think that is more harmful to cats than corn and rice as it causes wind but that's just my opinion. My cat gets the runs on stuff that contains peas. I don't know why people buy the 'no grain' slogans so much but then the second ingredient is peas.
Hope this is of help, xx
martina
Lilly's
https://www.lilyskitchen.co.uk/for-cats ... -our-rangeHi life
https://www.hilifepet.co.uk/cats/value- ... anq=id_365