It wasn't Erhu, it was Dahu who absolutely had no regard for himself. Old Mi felt a chill inside him—he'd actually always known subconsciously how his adopted son and biological son felt about him.
Asking the daughter-in-law to step in to pull them apart was even more inappropriate. Besides the need to avoid suspicion, there simply was no reason for a sister-in-law to intervene in dragging away an elder brother-in-law. Furthermore, Dahu was very likely to end up attacking his brother's wife along with everyone else.
As for asking Comrade Pei to take action—
Forget it, if he didn't see it wrong earlier, the boss's wife had been charging at Comrade Pei's wife... So it was inevitable that Comrade Pei would be angered. If he had wanted to intervene, he would have done so already. To ask for help again for these two who had thoroughly disgraced themselves and their family was shameless...