Is the tree shown a valid red-black tree?
You are correct $-$ the red-black tree you have drawn is not balanced.

For a balanced red-black tree, the number of black nodes between the root (including itself) and any leaf node (including itself) must be a constant. This is called the black height and should be a constant number that is the same regardless the path along which it is computed.

However for your tree, the path 00 results in a black height of $2$ and the path 1000 results in a black height of $3$. 0 = go left, 1 = go right.