"ek" in the lexicon is "out of, from, by, away from." John 17.15 is a different context. It is not promising no death, just to be kept from evil so the Christian does no evil and is not deceived by evil. A Christiana could still be killed at the handsd of evil Rev. 17. Whereas Rev. 3.10 is promising to literally be kept from the hour of the Tribulation itself based on a condition. This is a conditional statement. It's a promise IF YOU keep the word of His patience you will escape the hour of trial that is to come upon the whole world.You say "ek" has to mean "out of" in Rev 3:10, but I disagree. The Greek phrase "tereo ek", which is translated as "keep...from" in Rev 3:10 is also used here:
John 17:15 I pray not that thou shouldest take them out of the world, but that thou shouldest keep them from the evil.
Not all Christian "keep the word of His patience" so not all Christian will be kept from the hour of trial. But a spiritual Christian who keeps the word of His patience could yet be martyred during the Tribulation so the latter would not be kept from if he is martyred. Death is no blessing. The only way God can make this promise to be kept from is by being raptured. Whereas John 17 it is a being kept from evil and from doing evil. Even though this is God's wish, a Christian can still be martyred, that's why no promise was made to be kept from the hour of trial in John 17. Jesus doesn't need to remove you from the world in order to protect from trials and tribulations in Rev. 17, because there are many martyred Christians throughout the centuries. Whereas being kept from the hour of trial in Rev. 3.10 is a reward to overcomer believers who fulfill the condition by being watchful, prayerful (Luke 21.36) and keeping the word of His patience.Jesus was not praying that they would be taken out of the world and kept out of the evil world. He was praying that they would be protected from evil while still in the world. That is how the phrase should be understood in Rev 3:10 as well. In that verse Jesus was telling them that because they had "kept the word of my patience" He would protect them from or through "the hour of temptation, which shall come upon all the world". Jesus doesn't need to remove us from the world in order to protect us from trials and tribulations. In no way, shape or form can Rev 3:10 be used as support for a pre-trib rapture because it has nothing to do with anyone being taken off of the earth.
You've tried to mingle two unrelated texts just because they have the word "from" (a preposition) in them. Stick with the context.