The 'Mystic Focus' ability of Just Blade lets a character imbue their Grim Heritor with a single spell-like ability. The first circle of the Incantation track ('Incantation') is a spell-like ability, and is thus eligible. However, the second circle of Incantation lets a character sacrifice a spell slot and imbue their Incantation with a spell that has either a single target, an Incantation version, or both (in the last case, use the Incantation version); the spell is cast for free using the Incantation's attack roll whenever the character in question A. uses Incantation and B. wants it to go off.
So my question is this: can I imbue my Incantation with a spell, imbue my Grim Heritor with the Incantation, and use Mystic Focus to activate both? For example: imbue my Incantation with inflict light wounds, imbue my Grim Heritor with my Incantation, and then attack; do I deal melee damage, then resolve the effects of my damaging Incantation, then resolve inflict light wounds?