I think it is possible that the crew were unaware they had contacted the runway, the GO around was probably initiated during the flare when they noticed the unusual attitude from the lack of gear, by the time the engines had spooled up the nacelles just touched the runway, hard enough to damage them and the IDG's but not hard enough to be catastrophic or even erode the fan cowl latches (Fan cowls stayed on). This could be why they don't mention it or call a mayday until the IDG's and engines start to fail later in the go around due to the damage sustained.