There are countless dead-ends in development, and this is destined to be another. The plan being that if it could be got to fly, then the centre-body could readily be swapped out for the phone-box and mannekin ~ the reason in turn being that at this stage the two drones need to be hard-wired.
The eventual aim is to use two wholly independent drones top and bottom, with the payload sandwiched in between. In the near term though the upper drone will control the lower and this itself is possible because their is sufficient length in the wiring connecting the ESCs (or electronic speed controllers) for them to be commanded from a flight controller fixed above the upper drone. Meanwhile separate battery-packs would service the upper and lower set of motors so as to reduce the wiring loom.
In effect this could be though of as the brain up top, connected to the lower limbs by a form of nervous system... whereas in the long run we want something like a starling murmuration in which the lower drone works independently whilst in concert with the other.
After all that however I have formulated a better means of incorporating the phone-box with the two drones, and I shall therefore re-cycle the above in accordance with that plan. This is nothing new though, as the many iterations have been re-cycled endlessly as a way to evolve the most practical means possible of raising a body by electrical means.
Like Frankenstein's monster.