thank you for printing and sharing the photo
yes the design was not for the volcano heatblock. when i look at your photo, it seems that this heatblock is much longer in z-axis, than the original blocks.
the whole assembly, with this heatblock will probably not fit the printer as the nozzle will end up below the buildplate.
i dont have a volcano heatblock, but will order one, and adjust that the hotend mount is moved (up in Z-axis) to accommodate the increased heatblock height, and also that the part cooling fan is better aligned. Otherwise let me know what the exact distance (mm) is between hotend last fin and bottom of nozzle, and i will see if i can adjust.