Thanks for sharing your question about what bog to use on your timber rot. Generally, I recommend using Earl's 250ml Wood Hardener along with Turbo Builders Bog. This combination is often a good way to repair timber rot in window and door frames.
However, the damage to the corner of your timber roof frame is extensive and has gone past the mounting screws holding the other timber in place. In this situation, I suggest having the damage assessed and repaired by a registered builder as soon as possible. I don't recommend using bog on the damage as it is now structurally unsound.
If you need further assistance, please let me know.