"God distinguished Aaron by choosing him and his male posterity for the priesthood. His sons ministered in the sacred office. Nadab and Abihu failed to reverence the command of God to offer sacred fire upon their censers with the incense before Him. God had forbidden them, upon pain of death, to present the common fire before Him with the incense. 3T 295.1"
"And Nadab and Abihu, the sons of Aaron, took either of them his censer, and put fire therein, and put incense thereon, and offered strange fire before the Lord, which he commanded them not. And there went out fire from the Lord, and devoured them, and they died before the Lord."
The EGW passage directly recounts the events of Nadab and Abihu offering strange fire and being consumed, as described in Leviticus 10:1-2.
Aaron bore his severe affliction with patience and humble submission. Sorrow and keen agony wrung his soul. He was convicted of his neglect of duty. He was priest of the most high God, to make atonement for the sins of the people. He was priest of his household, yet he had been inclined to pass over the folly of his children. He had neglected his duty to train and educate them to obedience, self-denial, and reverence for parental authority. Through feelings of misplaced indulgence, he failed to mold their characters with high reverence for eternal things. Aaron did not see, any more than many Christian parents now see, that his misplaced love and the indulgence of his children in wrong was preparing them for the certain displeasure of God and for His wrath to break forth upon them to their destruction. While Aaron neglected to exercise his authority, the justice of God awakened against them. Aaron had to learn that his gentle remonstrance, without a firm exercise of parental restraint,…
"Then Moses said unto Aaron, This is it that the Lord spake, saying, I will be sanctified in them that come nigh me, and before all the people I will be glorified. And Aaron held his peace."
The EGW passage interprets Aaron's silence in Leviticus 10:3 as stemming from his conviction of neglecting his duty as a parent and priest. While not a direct quote, it expands on the meaning of Aaron's silence in the face of the tragedy.