A tree surgeon might have ladders but I think they tend to throw weighted lines and then climb hauled up ropes and I doubt they'd want to throw at a window. A window cleaner might have such laddders.
But, as Mavic_South_Oz says, the first good wind may knock it down so I think time is of the essence.
As it's near glass you can't throw stuff at it and a paid 'proffessional with laddders might want written permission from the management to put ladders in contact with the building.
Lory's idea sounds possible but might want three dowels, two to guide the baloon and a longer one to nudge the drone, you'd probably have to balance the 'nudger'.
Personally I'd be inclined to try nudging it with a stick/cane taped to the drone and use a blanket etc. held by two people to catch it. al la
As it is near glass I think lifting it with a drone would be difficult