Yes. This needs to be done. A high rated player whose account is closed already helps his team by giving everyone else a lower rated opponent. The adjustments should go as far back as necessary as well.
Adjustments for Closed Accounts

It would be nice, but it is a major time committment for the organizer.
I'll propose an alternative method that will save time since you don't have automated scoring:
- Implement an adjudication system where teams can submit an adjustment request if it impacts the outcome of their match
Then you can make the final decision if the adjustment is made.

I wanted to conclude this topic with a statement that because the Pan-American League is now included in the website developed by yneves for the World League standings (yneves.com/chess/#pl2013), the adjustments for closed accounts are now made automatically and will not need to be adjusted by hand by the league admins. Thanks, Yuri!
I would like to solicit your feedback on the idea of putting in a rule to provide for league match results to be adjusted to reflect player accounts being closed (for cheating, violation of terms of use, or some other reason). Our league rules do not address this, but if you feel it is necessary, we can do this. Such adjustments are done in the World League and the US Team Chess League, and maybe other leagues as well. Please share your views here.