How did the gravitational passage of the Sgr Dwarf initiate the collapse leading to our Sun's formation?

Its close passes through the galactic plane created shockwaves that compressed diffuse interstellar clouds.

The mechanism proposed does not involve the Sgr Dwarf matter directly becoming the Sun; rather, the dwarf galaxy served as a gravitational trigger. As the Sgr Dwarf plunged through the Milky Way's main disk, its gravitational presence generated powerful shockwaves. These shockwaves swept through the existing interstellar medium, specifically compressing large, diffuse clouds composed of interstellar gas and dust—the raw materials for star formation. This sufficient compression was crucial because it allowed gravity to finally overcome the internal pressure within these clouds, leading to the necessary inward collapse that eventually resulted in the ignition of our Sun.