To further explore his attitude of thoughtlessness, Grenville highlights the events where group of emancipists plans to clear dharug people in Myall Creek due to the ongoing conflict Involvement of massacre. does this make sense

No, the statement does not make sense grammatically or logically. It seems to mix different ideas and lacks clarity. It might help to rephrase it or provide more context.

The statement you provided does not make complete sense. It seems to be discussing the attitude of thoughtlessness depicted by Grenville and the involvement of a group of emancipists planning to clear the Dharug people in Myall Creek due to ongoing conflict. However, it is unclear how these two ideas are directly related.

If you would like a step-by-step analysis of the statement, here it is:

1. The statement begins by mentioning Grenville's attitude of thoughtlessness.
2. It then highlights a group of emancipists planning to clear the Dharug people in Myall Creek.
3. The reason given for this planning is the ongoing conflict.
4. The involvement of a massacre is mentioned, but not expanded upon.

In order to clarify the connection between Grenville's attitude of thoughtlessness and the events surrounding the Dharug people and Myall Creek, more context or information would be needed.