Your success was not su much luck as good play.  You used the Crowns (and Blaster) to turn a 4-letter word into a 10.

Good job!

My 10-letter word on that level was an actual 8, with 4 Crowns which would have counted as a 12 if that were required.  My play focused on loading the board with Crowns and saving the good candidates words on one side.