Penalty needs to be increased.
Count it as a loss for MMR.
Make the dodge timeout only count down while you are logged in.
The problem is smurfs. They unlock only the most OP champions, and dodge when they roll a free week, just so they can hop onto another one of their many alt accounts and do the same thing again. They scum for OP rolls like this until they get one, because they have no skill or the ability to win on their own. Counting dodges as losses would force them down to their proper MMR, so most legit players would never have to deal with them, and the forced-login penalty prevents the account-hopping.