What should I do regarding someone who interprets the Hadith "they never did any good at all" literally, given Ibn Khuzaymah's interpretation that the negation refers to the imperfection of their deeds, and given the Hadith about the killer of a hundred souls, concerning whom the same phrase was said despite his repentance?

The Prophet's (peace and blessings be upon him) saying: "They never did any good whatsoever" in the hadith has two meanings: 1. That they did not perform any physical acts of worship due to an excuse that prevented them from doing so, such as dying before they were able to perform them. 2. That they did not perform the deeds perfectly and completely, for true faith necessitates physical acts of worship. So, whoever is truly a believer, that must manifest in their deeds, and whoever does not do anything is a disbeliever.

Muslims enter Paradise through faith, but faith must be accompanied by action. Whoever does not pray is a disbeliever and will not enter Paradise.