After your suggested edit is submitted, a 2000 user cannot begin their own edit without reviewing yours: if they click edit (1), instead of the regular editor the system brings up your edit for review. I just experimented with this myself:
Pressing Skip here returns the user to the question window without any changes. Any of the other four buttons will constitute a review of the suggested edit.
However, if a 2K user begins their edit prior to you finishing it (and finishes it before your suggestion is fully approved), your suggestion will be rejected. The conflict between a suggestion and a real edit is always resolved in favor of the latter. See Can we get a better conflict resolution to edits vs suggested edits.
- You made your suggestion at 18:08:15
- A 2K user posted their edit at 18:08:41; this resulted in the rejection of your suggested edit.
Chances are they began editing before 18:08:15.
- Question was asked at 21:28:05
- Your edit was suggested at 21:31:16
- It got one approval vote 21:32:52 (one of two required votes for approval)
- The author edited their post at 21:34:51; this resulted in the rejection of your suggested edit.
It seems that the author noticed a problem with their question immediately after posting, and began editing it. Their edit was more than just formatting, so I understand it took a while to type. The author of a post has the privilege to edit it directly, so the edit conflict was resolved in their favor.