Despite how scary this sounds, most companion animals are unable to get into a large enough amount of plant material to cause systemic signs. (aspcapro.org)
Dogs showing systemic signs and dogs whose tumors return after surgical removal have poorer prognosis. (caninecancer.com)
Furthermore, none of the causes of uveitis are particularly likely in a dog of this signalment, and the ones that are reasonably possible (such as infection) would primarily present with systemic signs of illness as well. (dogingtonpost.com)