I understand you did this with the best intentions, but my experience is that hanging a new, or repeating question at the end of an old thread is seen by less people then a new thread. And the older the thread, the more of the original contributers will have stopped their supscription to the thread
It depends of course much on the way the potential helpers use the forums. And they use different methods.
When they do look at every new post (there is such an option in the forums) they will see it. But many don’t do that because that list also has the non-English posts.
You can use RSS feeds on the forum sections you like, but those will only offer the new threads.
Regularly clicking on the sub-forums you like to see what is new at the top also only delivers new threads.
Other may use other methods I even do not know.
I hope you understand that the best way to advertise the most important questions, your questions, is by having a new thread in the best fitting sub-forum with a good title that invites the best gurus to see and open it. lol!