After a few years I seem to have come back to the topic of the possibility of tidal locking on a planet with life. I love speculative biology and designing these sorts of scenarios but tidal locking I've never been able to find a solid answer to it's ability to support life.
In a post a few years ago, someone suggested that a low speed collision could cause tidal locking with the right speed and angle of collision and wanted to follow up on this in more detail. So on to the question at hand, this is a scenario I've come up with to determine if this is possible; early in the life of a planet orbiting a K-class star in the goldilocks zone, a rogue planet collides into the primary planet at low speed, approaching from a counter-orbital angle. The collision isn't head on but the rogue planet mostly scrapes the surface, then pulled into the other planet due to its gravity. The primary planet is young, but largely at the end of it's molten stage (or soon after depending on the fidelity of the situation). The collision has enough force to slow the planet into a tidally locked orbit around the K-class star.
Would the planet in this scenario be able to support life after this event and stay stable? The core, I would assume, would still be active for a long time, as well as the magnetic field. Although I know more about biology than astronomical bodies so many of these ideas are new to me.
Edit: the time between the planets collision from the formation of the planet would be about 200 million years, tidal locking would be completed after about 2.5-3 billion years(?), with life forming around 1.1-1.6 billion years after the collision.
My apologies for any weird wording of things as well, if anything needs clarification or to be reworded I will gladly do so!
Edit: To clarify, I am asking if a planet tidally locked by a collision, can still support life and stay stable for the foreseeable future.
Edit 2: removed redundancies.
Edit 3: removed the part about the planet not being fully absorbed.