"The enemies of the present truth have been trying to open the door of the holy place, that Jesus has shut, and to close the door of the most holy place, which He opened in 1844, where the ark is, containing the two tables of stone on which are written the ten commandments by the finger of Jehovah. EW 43.1"
"And the temple of God was opened in heaven, and there was seen in his temple the ark of his testament: and there were lightnings, and voices, and thunderings, and an earthquake, and great hail."
The EGW passage directly references the ark of the testament and the opening of the temple, key elements of Revelation 11:19, within the context of her understanding of the heavenly sanctuary. The connection is more than thematic; it's a specific interpretation of the verse.
"Satan is now using every device in this sealing time to keep the minds of God's people from the present truth and to cause them to waver. I saw a covering that God was drawing over His people to protect them in the time of trouble; and every soul that was decided on the truth and was pure in heart was to be covered with the covering of the Almighty. EW 43.2"
"He shall cover thee with his feathers, and under his wings shalt thou trust: his truth shall be thy shield and buckler."
Both passages use the imagery of being covered by God for protection. Psalm 91:4 uses the imagery of feathers and wings, while EGW uses the imagery of a covering. The core idea of divine protection and refuge is shared.
"Put on the whole armour of God, that ye may be able to stand against the wiles of the devil."
Both passages speak of protection against spiritual attacks. Ephesians 6:11 uses the metaphor of armor, while EGW uses the metaphor of a covering. The underlying theme of divine protection against Satan's wiles connects them.