That's just a second instance of the same locking mechanism; it wouldn't fix the problem that such a mechanism doesn't always work (when the load on the DB server is very high, is my guess as to when it doesn't work - such that writes from one thread can't be relied upon to have made it to the db in a defined+short amount of time).
If you are having this problem consistently (i.e. you can reproduce it), then the best thing to do would be to report it as a bug in the WordPress core bug tracker. Then you could work with the guys who wrote+maintain WP's scheduling system to get a solution that would be a solution for *all* scheduled tasks (rather than having a localised work-around in just one plugin).
David