Wow, worked like a charm! I'm not sure how often I'll need this capability, since we have gotten accustomed to this reactivation not being possible in WorldServer. But now that I know it is possible, I'll be sure to keep it in mind if the situation arises. Thanks!

No worries, this solution uses something i was unaware of for a while as well and i consider myself to be quite a knowledgeable WS customer. My solution uses the project update capability that has been in WS for a while and is found in the SDL doc's here: https://tinyurl.com/jhnq5e7. What you have to do is trick WS into thinking that the source has changed. What i do is download the source from the explorer (or the tasks page) and then open it, add a space, save it, remove the space, then save it again. Then i upload this newly saved (but identical source) and overwrite the original source file in the explorer. Once this is done you can schedule the task(s) to be updated (you have to do so per language). To do this on the tasks page you change your view to show tasks with changed assets. Once you select this you will see an update button. Once you click it. The tasks will start over in the workflow that the project was created with.

It's not the best but is better than nothing.

@Eric Bishop: I didn't know that. As of which version is this possible, and what do you need to do? I assume that something in the configuration files needs to be changed, since even as an "all-powerful admin" I don't see anything about this anywhere in the browser interface.

This actually is possible with some caveats if the project still shows up under completed and canceled.