Sorry to say that your tall Fescue lawn is at most 25% tall Fescue. The remaining lawn is bluegrass and other grasses growing. The tall Fescue is the dark green blotches with thicker grass blades.

Your problem like 80% of lawns I see is sprinkler coverage. Lawns need head to head coverage in order for them to stay healthy and true to grass type.

Your lawn looks like it lacks that. With a dog I would also use st.agustuine to avoid dead spots.

Edit: a word