I'd prefer that too :/
Unfortunately, only mods can do that.
See this feature request on Meta Stack Exchange.
When I want to find the review of a post, I look at the review history page and scroll through the recent pages to find the post I want (Ctrl+F is helpful), but this page only shows the history of reviews by everyone to users who have >10k reputation - otherwise it shows you your own reviews only, which is not helpful for this purpose. This also doesn't work if nobody has reviewed the post yet (for example, it received close votes from users who landed on the page; some questions get closed before anyone reviews them in the queue, but in such cases the closure is usually correct).
Only completed reviews are accessible in the post's timeline, so that also does not help.
In short, there is no easy way to vote to Leave Open from a question page. If you post the question link in the Downboat I or someone else will be willing to look for it in the history or let you know if we encounter it in the queue and give you a link.