It should take 25-30 seconds for the stabilator trim to run from full up to full down, so given he stalled at only twenty feet, chances are he may have had the trim set incorrectly rather than have experienced a runaway trim. His serial number is 120185 so it's an older kit. I started building mine at the end of 2010 and mine is 120346. The Production Acceptance Procedures for the RV-12 are quite detailed and thorough, so any trim malfunction or common builder's error such as having the trim wires reversed should have been picked up either by the builder or the DAR at sign-off. I understand the Lismore 12 got to about 200 feet before he pulled up steeply. The trim can be over-powered by the pilot, but it needs a pretty firm push/pull on the stick, and if he wasn't expecting it, he wouldn't have had much time to react. Another common cause of this type of accident in the RV-12 is forgetting to latch the canopy. His early kit would not originally have had the audible canopy latch warning that the later kits had, although he could have retro-fitted it.