You should probably just focus on the RC kibble and wet L/D for now. Apple bits are good b/c of the pectin for his tummy. Watermelon is good to drizzle the Lactulose on so he will eat it and good for added water content. Romaine lettuce is good b/c of the Vit. K it posses which is good for blood flow
Once he is getting better and test results are getting better you can look into treats. You just don't want him to get 'picky' about his RC and L/D food - b/c treats taste better
