One solution may be to calling to see whether the itinerary can be changed to DXB-HKG-PFT. PFT is the ferry terminal in central Guangzhou - much more convenient, assuming you are heading to city centre/canton fair and stuff. The connection works perfectly and you will be in central Guangzhou at 2pm... You don't need to clear anything in HKG as it is "airside" transfer and luggage will be sent through - so in fact overall this is faster (and easier) than high speed rail.
Given both PFT and CAN are Guangzhou, the agent MAY be able to change for you (there may be a fare difference though).