Pete,
that's a really great question!
In previous years, the impact of Model Damage has typically been evaluated right away at the time of the damage. This year, because of the free rescue capability, the possibility of scoring can be deferred until later in the match.
My first inclination is to say, no, it isn't okay. A team that obviously benefited from earlier Model Damage to the Obstacles would not earn a higher value for the mission. Any points from the Obstacles mission that were earned prior to the damage or without benefit of the damage (if that were possible) would still be awarded to the team. Rule 34 prevents a team from increasing its score as a direct result of causing Model Damage.
This opinion may be revised by a future Game Update, as always.
Steve Scherr
VA/DC FLL Referee Advisor