"Infinite layer" nickelates (ILNs) cal RNiO₂ (cal R=rare earth), having empty apical O sites, become superconducting upon hole doping, stimulating research into the related sequence Ndₙ₊₁Ni⁺ᵖₙO₂ₙ₊₂, formal charge state p=1+1/n, n=2,3,4,...., with the n=5 member being found to be superconducting. The two layer system La₃Ni₂O_(7-δ), with δ=0,1/2,1 (p=2.5,2,1.5) approaches the peak in the nickelate superconducting dome but shows no superconductivity. Newly reported La₃Ni₂O₅F reaches the Ni¹⁺ goal while, as we show, introducing a partially occupied electron band E^*, based on an interstitial density that extends over the three open "apical" layers and leads to a single cylindrical electron Fermi surface giving self-doping. The commonly inert Ni d_xz,d_yz orbitals partner with interstitial E^* to provide an incipient non-analytic Dirac point, with the critical point being reachable by pressure or further F insertion. The E^* electron cylinder and the conventional Ni dpσ hole carriers combine to provide a two-fluid dichotomy of hole and electron quasiparticles, affecting normal state properties that should verify the dichotomous aspect of transport.