He asks: “Can the healing intentions of the estimated 100 billion other galaxies also be requested and used for healing work?” What can Creator tell us?

The energy within other galaxies is off-limits, with respect to the ongoing contest for power and control over humanity and the other worlds in your Milky Way Galaxy, so this is a local problem that must be dealt with locally by beings in the physical in the lead but reaching out to the divine realm, not to other worlds in other diverse locations or planes of existence outside of your galaxy.