Well, I was tagged here so I guess that I will chime in with my experience and what worked for me.
Having dealt with Dino's in the past, and a heavy infestation, I learned that they do not like high Ph or high temperatures. Particularly, a higher temperature.
Combined with the standard tactics of combating them as you have listed, raising the tank temperature to 82-83 degrees for a few days did the trick for me. Apparently, Dino's have a hard time reproducing in a higher than normal temperature. Care must be taken to safeguard you're inhabitants but if all else has failed try increasing the temperature.
As
@gbru316 mentioned, the Coral Snow mixture may help to bind up some of the free floating Dino's. In the past I have used the Coral Snow along with a canister filter running a very small micron filter(1) to help grab everything that was being bonded up to the snow.
-Sonny