Is this possible?

Purchase 1 Litre of Duty Free in USA at airport (all bagged/tagged and airport sealed)

Fly from USA to LHR T5 with Duty Free as Hand Luggage

Go Landside to the Arrivals Lounge (with Duty Free in hand)

Then go back Airside LHR T5 to catch internal flight to Manchester (with Duty Free in Hand)

Duty Free remains bagged/tagged and USA airport sealed and I would have original receipt as well

Will it get the BAA Moisture Goons approval as certified/safe 'wet' Hand Luggage for my LHR-MAN flight? or will they just laugh at me and either take it off me or make me drink it beofre going airside ??

If NOT is there anyway upon arrival that I can pass it to a BA person so that they can deliver it to the CR (where I can pick it up once airside again ??)