A simple task.
Go back to the last 5 discussions. Ask if the creator (original poster) resolved their problem.
If the answer is yes, ask if they wouldn’t mind sharing in that discussion that it solved their problem. If the answer is no, ask specifically where they got stuck.
This achieves 4 things:
1. It shows to future readers whether proposed solutions helped, how well it helped, and in what context it helped.
2. It lets those that replied know they resolved their problem. They feel better about responding. Or it lets them know that their information works in specific contexts in case they reply on a similar topic in the future
3. You can bring back people who didn’t get a satisfactory response (and tag in other experts who might be able to help).
4. You also get a sense of the task completion (or problem resolution) rate. Are most people not returning because they got the answer they were looking for or didn’t get the answer they were looking for.
The number of discussions is very much arbitrary. The more time and volunteers you have, the more frequently you can check in to ask if the responses resolved their problem.