She is willing to prostate herself before Henri Pichot because she is willing to do anything that will help her son to die "like a man" rather than "like a hog," as was said during his trial. Having worked for the Pichot family in the past for many years, she now in Chapter 3 comes to ask Henri Pichot a favour: that he will use whatever influence he has to ensure that Grant is able to go and take her place to visit her son so that he can learn what it is to be a man and he can die like a man. Note what Miss Emma says to Henri Pichot in the following quote:
The law got him, Mr. Henri... And they go'n kill him. But let them kill a man. Let the teacher go to him, Mr. Henri. I done done a lot for this family over the years.
Miss Emma is ready to prostrate herself and beg therefore in order to secure her objective, which is to gain permission to allow Grant to visit her son so that he can educate him and turn him from a "hog" into a man so that when he dies he will die as a man.