Hello, and welcome.
Thank you so much for your patience; I'm sorry you did not receive an earlier answer. Various experts are online at different times and I recently logged in and read your question.
I'm so sorry to hear that Dingo is not feeling well and has all these symptoms. While toxoplasmosis gondii is a possibility, this must be tested for, by the vet, in order to be 100% sure.
If Dingo spends time outside, hunts/eats rodents and/or spends time with other, possibly infected cats, these are the main avenues through which he could contract toxoplasmosis gondii.
Here is more information about the disease:
Since he was diagnosed with early kidney disease, this is a progressive condition and especially in older cats, may move more swiftly if it is not treated properly with diet and sub-Q (under the skin) fluids on a steady basis. He may have an eye infection or a scratched cornea, causing the tearing from his eyes and this needs to be evaluated by his vet, asap. I don't know how long ago his last vet visit/lab work was done, but if he hasn't improved or these symptoms are more recent, I strongly suggest another vet visit and blood work at this time, to determine the causes of all his symptoms and then, the vet will treat each one, as needed.
I hope after he's seen and treated by the vet, Dingo will be feeling much better!
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