I don't think you should lock the RR 99 thread. There's still the matter that some people may want to report 100% for some of the levels, plus there are other things people may want to comment on. Just let it go cold naturally like any other threads.
One thing I want to comment on for the RR 99 thread is, I would be a little wary if any of the results reported had only been done on Lemmini and the solution has timing-critical parts. The problem is I don't know how "trustworthy" the timing of various things are in Lemmini. I know all the results ClamSpammer and I have reported on that thread are DOS Lemmings/Lemmix, so it'd be good for other people to comment on which levels they've reported results on using only Lemmini, or confirmed that all their results were done on Lemmix/DOS Lemmings. Personally I would've kept "Lemmini-only" levels on a separate list, but regardless, if there are levels that somehow only work on Lemmini they definitely should be called out as such.