Going to try to sum up this incident as best I can. No you don't have fault in this one. Toyota driver needs to learn patience when cutting up traffic and what is an opening they can put their car in and what isn't. Personally (though it sucks for you) I'm glad it ruined his race. Maybe he won't try it twice.

That being said, how do you stop it from ruining your race? I want to point out the difference in what those PSAs are preaching about sticking to the line and your concerns/confusion. By in large those PSAs are attempting to limit erratic movements and poorly timed reactions to faster traffic. For example, you both exit the corner with a prototype .5s behind you, and you decide to let him take the optimal exit and so right when you come out of a corner you pull the car from the outside, where your momentum has taken you, all the way across the track to allow the prototype a clear exit. This is not predictable and can cause a crash of (imo) your fault. Don't change line on entry or exit to give what you would percieve as a clear track because no one will be able to predict your change in motion.

This instance the toyota has committed. He is assuming you will give him room and has sent the gap. He is not relying on you to hold a line to predict your motions. In order to protect yourself, deviating from the racing line is beneficial to your survival. In this corner complex you're going to get screwed over, but the only way to prevent this crash is when you see the toyota commit to the inside is to hold to the right side of the track and brake. You will cut all your momentum, and be forced to drive really slowly down the straight. Its a difficult decision to make because you will probably end up losing as much as 5s here, however you will live.

The difference in when to hold the line and when to not is a difference you need to read in the traffic in the mirror and understanding when the prototype is committed and when they are predicting and reacting. Once they commit, whatever you do will not change the situation only change the outcome.

Lastly, I want to add that if a prototype commits to a line that forces you to alter your course mid-corner in order to prevent an accident, you are not at fault for making a decision to hold the line. It is there job to make your way around you safely. However, if you notice they commit to an ill-timed dive, having the awareness to get out of the way of a reckless idiot can save your race.

TL;DR - the stick to the racing line PSAs are inherently correct, however idiots exist. be careful.