Kriya Yoga, strikes me as somewhat as a modern myth. The practice is certainly effective and I would say it is probably the most powerful type of Yoga of our time and the most scientific. However, the history of it strikes me as fabricated, probably to market Kriya Yoga to people. In India, many new spiritual works or traditions have often claimed that their lineage is very ancient going back to Vedic or pre-Vedic times, such as the Yoga Vasistha ascribed to the Sage Vasistha - or the Samkhya Sutras asribed to Kapila. However, historians often find that these histories are constructed and they are of a more recent origin.
The biggest tell-tale sign I have read is there does not seem to be any precedent for Kriya Yoga prior to modern times. All writings by Kriya yogis rely on new interpretations of scriptures to suggest that Kriya Yoga is hinted by them or mentioned by them, but its a very esoteric and secret science that only initiates knew. They even claim Jesus was an initiate. Then there is the myth of Babaji, which also has no precedent in ancient times, but fits in very neatly with the modern mythological culture of ascended masters and secret orders and societies.
Thus my likely guess is that Kriya Yoga is a modern tradition, not ancient. The myth of the ‘ancient’ has just been used to market it.