Is prostrating oneself absolutely to Allah at any time, with the reported supplications, based on the Hadith: "Help me by prostrating much," sound or an innovation?

The basic principle concerning acts of worship is tawqif (strict adherence to what is legislated). A singular prostration is not legislated unless it is a prostration of recitation (sajdat al-tilawah) or a prostration of thankfulness (sajdat al-shukr). Whoever innovates something in the religion that is not part of it, it is rejected. A singular prostration [performed independently] is an innovation (bid'ah). Acts of worship are based on divine legislation, not on innovation. Scholars have agreed that a singular bowing (ruku') is forbidden because it is an innovation. Furthermore, one is not rewarded for an innovation, and it diverts one from the Sunnah.