I would like some clarification on this topic. First of all. Did they replace the valve cover gasket or head gasket? A head gasket problem is usually low compression and loss of coolant. A valve cover problem is usually loss of oil as stated. Many people mix up the two.
From what you are saying, It looks like you had the 110,000 service done which is the timing belt, water pump, cam seals, which sounds routine. I can see a valve cover gasket at this time, but a head gasket is not routine and would cost $2000-3000+ for a dealer to replace.
The best way to determine where the leak on the floor corresponds to the area underneath. there are so many things that can leak oil. An oil filter, oil pan, oil pan bolt. distributor o ring, oil pressure sensor, crank pully seal. It’s endless. It may be possible something is leaking from the previous repair, but most reputable Honda dealers should check their work for free if you bring it back.
– John (I have had 1: 94 1: 96 1: 97 1: 98 2: 99’s 2: 03’s 1: 04 1: 07) Accord