Here's an article that relates the modern surya namaskar to specific rituals with vedic origins, focused on praising Surya. It also points to multiple historical references to prayer/excercise like ceremonies practiced well before Krishnamacharya's time.

And other documents that indicate the complexity of hatha yoga practiced before Krishnamacharya have been found in the Mysore Library, having been referenced by Krishnamacharya himself. This is discussed in the following article in Yoga Journal which I will also excerpt here:

"as the Sritattvanidhi proves, the Mysore royal family's enthusiasm for yoga went back at least a century earlier. The Sritattvanidhi includes instructions for 122 yoga poses, illustrated by stylized drawings of an Indian man in a topknot and loincloth. Most of these poses—which include handstands, backbends, foot-behind-the-head poses, Lotus variations, and rope exercises—are familiar to modern practitioners...This is the first textual evidence we have of a flourishing, well-developed asana system existing before the twentieth century—and in academic systems, textual evidence is what counts...The manuscript points to tremendous yogic activity going on in that time period—and having that much textual documentation indicates a practice tradition at least 50 to 100 years older."

The article also indicates that the breath linked vinyasas were taught to Krishnamacharya by Ramamohan in Tibet. What I take away from this is that The lineage handed down to Jois, Desikachar and Iyengar was one of hybridization between different extant forms of esoteric physical yoga practice. Many traditions in India existed solely through oral tradition, often guru-to-disciple and become difficult to date accurately, as we see with the Vedas.

As often as I hear these claims about european gymnastics inspiring Krishnamacharya, I have not yet seen anyone furnishing evidence of a notably similar gymnastic tradition.