At about the same hours I had the front nose wheel fail to lock down on a PA28R, it was due to the Hydraulic Ram literally cracking in two, Fire Engines out at Manston etc.
I did not know the reason but it locked into place due to gravity when I slowed right down on base to final turn (thankfully) but lets just say I was well out of my comfort zone, performed a pretty crap landing not to be proud off.
I say well done to a Pilot who would have been under considerable stress!!