As reading Mike Turner's article below shows, zero point energy density and its equal and opposite pressure, together directly warp space-time. This is different from QED based on globally flat spacetime without any gravity at all in which to a rough approximation you can ignore energy scales and simply subtract off the virtual photon zero point energy density with "normal ordering" of the photon creation and destruction non-Hermitian operators. See Milonni's book "The Quantum Vacuum" for these details, which ignore gravity effects.
Hal needs vanishing zero point energy density inside the EVO shell with an enormous zero point energy density outside the shell. This immediately falsifies his model, apart from the other issue that he needs a positive external pressure to hold in the Coulomb repulsion of the N electrons making the EVO thin shell. Casimir was not aware of the general relativity constraints on the problem. Casimir's Type II model would require that we live in an exotic vacuum where /\zpf ~ (mc/h)^2 ~ 10^22 cm^-2. In fact the vacuum we live in has /\zpf ~ 10^-56 cm^-2. Indeed the Casimir-Puthoff external /\zpf would not permit our universe to exist! It would warp space-time too much! In fact the EVO needs a negative pressure inside its shell with /\zpf ~ 10^-56 cm^-2 outside it where we exist. How come the non-exotic vacuum has such a small /\zpf? Simple, the vacuum coherence ABSORBS the random ZPF into the VACUUM CONDENSATE as a kind of zero entropy superfluid reservoir. The random ZPF is analogous to the "normal fluid" excitations. This also solves Penrose's problem in "Fashion, Faith and Fantasy" explaining why the early SPATIALLY-FLAT (on large-scale only) inflationary universe has low initial thermodynamic entropy setting the direction of the Arrow of Time of irreversibility of the Second Law of Thermodynamics to point the same way as the expansion of the universe.