Let's say for an example that two moderators moderating the same game hasn't been active for three weeks with one moderator being last active last year. What would happen if my submission hasn't been accepted/rejected for many weeks?

Just asking.

From the inactive moderator request page:

"Moderators are considered inactive if they have not logged on or verified a pending run in at least 21 days. In the case of inactive game moderators, please attempt to contact them via social media to resolve the situation. If a Super Moderator is inactive, we require other moderators to perform a substantial amount of effort themselves in reaching out to these inactive Super Moderators in order to request that they remove themselves first.

If a game's moderators are highly inactive (have not logged on in three or more months) and not responding to off-site contact, and you have a run already on the boards, you may request moderation of the game without a pending run. Accepting these requests are at the discretion of site staff. In terms of requesting the removal of inactive Super Moderators, the removal of inactive Super Moderators should be requested by other moderators of the same leaderboard."

https://www.speedrun.com/knowledgebase/supporthub/request-moderation