The significant amount of times in which Kempe had been accused of Lollardism by her peers and Church officials seems to indicate that they at least would view her as outside the normative practices of the day. For a person in Kempe's position (wife, catholic, mystic) she had enacted in many roles that were outside the acceptable view.
A significant position clarification was made in chapter 52 of The Book of Margery Kempe that may lead the reader to infer Kempe's own adherence to Catholic sentiments and pull her away from the accusations of Lollardism. In this chapter Kempe argues with an Archbishop on the validity of her position in engaging with the public in a role of spreading God's word. The Archbishop attempts to make Kempe swear " that you shall neither teach nor challenge the people in my diocese." This oath that the Archbishop wishes Kempe to make creates a problematic situation for readers since Kempe has not expressed anything of what she has taught specifically.
Kempe is said to have spoken OF the gospels on her pilgrimage, has spoken to many Church officials regarding the secrets that God has given her, and has discussed her visions. The actual teaching of the Bible/theology/dogma has not occurred during this point in the book. However Kempe is quick to deny the oath that the Archbishop is requesting but her explanation does not include teaching at all instead: "I will speak OF God and reprove those who swear great oaths, wheresoever I go, ...".
The significance of this statement is that Kempe is not being chastised because of her audacity to teach, but that she is making officials uncomfortable with her stance upon oaths spoken by men. Speaking to the Archbishop this would cut to the quick of his own office in which he had to take an oath unto God. Kempe is seen throughout the text reprimanding those whom are in a position of divine power and do not live up to the position given to them. The Church officials that are reproved by Kempe have not lived up to the standard in which God has demanded of his representatives.
Hornbeck in his book regarding the markings of a Lollard would indicate that such a challenge would be the sign of a Lollard. The Lollard would hold a skeptical view upon the individuals in power give by the church, they would hold them accountable to live a standard of life dictated by God. If they did not live up to that standard then they lose all power and rights to that position.
Kempe does not make the accusation of the Archbishop not living up to this standard, but her refusal to give an oath and specification upon oath giving in general would dictate the focus she is pursuing.
An insightful reading of this, especially in your saying that "that Kempe is not being chastised because of her audacity to teach, but that she is making officials uncomfortable with her stance upon oaths spoken by men." It is her disruption of male authority which puts her in some hot water, and in fact her refusal to partake in the same sort of discourse (oath giving etc).