Eko is not stupid enough to commit a crime that will leave evidence behind.
If Eko did that, wouldn't Eko be caught by the police a few days later?
What about the money that Haikal has given? What about his wife?
Eko did that to get rid of his problems, not to add to them.
Although Eko will only result in financial losses. Because Eko has never done anything that violates the law. Eko needed time to convince himself.
This is Eko's only chance to pay off all his debts. After paying all the debts, his wife might be willing to forgive Eko.
Eko's life can return to normal.
After successfully convincing himself, Eko finally agreed.
With help from Haikal, Eko manages to set fire to the pharmaceutical factory at night.
Bagas knows about this incident because Bagas has read the novel.
Even though Bagas only knows a little about the plot, Bagas feels that this is enough to defeat the Protagonist.