I drive redi-mix, i'm not getting a good enough picture of the area to say for sure but i wouldn't advise going on that driveway that i know. If a guy and dumped some gravel in the ditch maybe could get a straight shot across it? the trucks are very top heavy and don't do side hills well. we have deflaters that really help a lot in yards not to sink in, plus wheel locks and diff lock.
if it were me, i'd also opt for air entrainment if freezing is possible and a water reducer as mentioned above by someone. plasticiser, super, glenium, whatever trade name they call it around your place. even if the trucks throw in ten-15 gallons at the job to return slump after transport, its still overall less water in the mix.
they can pump low slump, we pump 2.5-3". highest slump you'd want is a 5 but with glenium or z-60 it would work like it's wetter. z-60 is a slump retainer, your guy should be able to advise on admixtures.
oh, the pump guy can put the hose into the last truck and pump leftover and slurry into it to eliminate a huge mess on your property.
to sum up my rambling you'd probably have 2-300$ in power buggy rental, i'd probably try to pump it.
post up some pics when you get it done
More thoughts, when we deliver line mix it's a smaller aggregate due to smaller line hose, not what I,d want. Also a truck shoot dumping would most likely not be able to reach the trench all the way around. Tempting you to add water and try to get it to flow or shoot across. Again, not ideal.