Were dinosaurs present on the planet prior to the first group of humans in existence or introduced in between the two human creation events?

The dinosaurs were introduced in between the two human cohorts. This was a relic of the Anunnaki era and was, in effect, a recapitulation of the Anunnaki presence, karmically speaking. In a sense, it was an outgrowth of the energies they brought to the Earth to have a hierarchy of power and control that reigned through savagery. In a sense, it was akin to a healing for Gaia as happens for human, having serial incarnations during which a similar struggle might reoccur again and again to have an opportunity to purge the original negativity and bring healing to bear to remove, eventually, the last vestiges of what was out of alignment. In a sense, this was the easiest way to heal the earth following the ravages of the Anunnaki and their presence.