I don't want to be rude but since you have some reliable contacts, can you please ask them, why did they leave this forum? They were very active till 2020 and I am sure this forum played a role in their success, I simply don't understand why they left this forum while almost every competitor is still here.
I have to say it is unfortunate to see them inactive, started from when they stopped the signature campaign few years back.
Actually they can hire someone to handle and manage their ANN thread, they have some staffs as support so I think one of them can be asked to manage this thread.
I believe it is not that hard to do it, showing activities by bumping the thread with some news such as promotion or updates regularly will be better than nothing.
Of course many people wondering about their inactivity, but I believe they are not leaving this forum completely.
OP was online yesterday, means that they are still monitoring their ANN thread but rare to post something here.