I think they serve two different functions, according to their placements. TDS is sort of the entry point to the Recovery Forums, where people are facing intense problems but don't necessarily have a recovery pathway yet. MH is more for people already on some kind of treatment plan, medication, etc. I know it's not always that cut and dry but mostly that is how I would delineate them based on their forum guidelines.
Which would mean that TDS suicide thread might contain more triggering content for people who are already in mental health recovery because the people in TDS, although just as wise, may not have any structured plan in their lives yet for getting better. It's sort of like "I'm suicidal because I'm addicted and out of control" vs. "I'm trying to get better but it's really damn hard and that's why I'm suicidal". MH is sort of the intermediate forum where people are trying to get better, and SL is where they hope they stay better. They are all safe spaces for different things.
Make sense?
FWIW, I would be open to merging the two, the problem is that placing it in TDS means people in MH and SL would have to go there into the trigger zone to post to it.
