The CYGNO collaboration is developing next generationdirectional Dark Matter (DM) detection experiments, using gaseousTime Projection Chambers (TPCs), as a robust method for identifyingWeakly Interacting Massive Particles (WIMPs) below the NeutrinoFog. SF6 is potentially ideal for this since it provides a highfluorine content, enhancing sensitivity to spin-dependentinteractions and, as a Negative Ion Drift (NID) gas, reduces chargediffusion leading to improved positional resolution. CF4,although not a NID gas, has also been identified as a favourable gastarget as it provides a scintillation signal which can be used for acomplimentary light/charge readout approach. These gases can operateat low pressures to elongate Nuclear Recoil (NR) tracks andfacilitate directional measurements. In principle, He could be addedto low pressure SF6/CF4 without significant detriment to thelength of 16S, 12C, and 19F recoils. This wouldimprove the target mass, sensitivity to lower WIMP masses, and offerthe possibility of atmospheric operation; potentially reducing thecost of a containment vessel. In this article, we present gas gainand energy resolution measurements, taken with a Multi-Mesh ThickGaseous Electron Multiplier (MMThGEM), in low pressure SF6 andCF4:SF6 mixtures following the addition of He. We find thatthe CF4:SF6:He mixtures tested were able to produce gas gainson the order of 104 up to a total pressure of 100 Torr. Theseresults demonstrate an order of magnitudeimprovement 1 in charge amplification in NID gasmixtures with a He component.