I must confess to raising an eyebrow as to density altitude being the cause of this incident. My experience with DA was on a midday takeoff in a PA-28 140 with 3 on board at Nairobi Wilson in a temperature of 32 degrees C. Full tanks of course. It was a VERY long takeoff and it was only afterwards that we worked out the DA was up near 8,500 feet. You start at an actual height of 5,500 feet above sea-level of course. The only redeeming feature was that a Lufthansa crew with 4 pax went through the fence in a PA-28 Arrow a couple of weeks later. Nobody hurt fortunately.
Many years later I was in a group on a Cessna 172 at Denham and having flown and filled her up, one of the other group memebers plus 3 friends and bags were about to depart to the IOW. It was quite a warm day so I asked if they'd checked the DA and they looked at me as though I was barmy but once again they only JUST got off so DA can bite in the UK.