Dawood "15:9 is simply a statement of fact that indeed God revealed the Zikr=the reminder (another name of the Quran) and He is its Guardian. When we read Quran (in prayers or otherwise), we are reminding ourselves of God, His attributes, His instructions/injunctions to us, etc., in other words remembering Him. When we actual follow God’s injunctions, Quran calls it Taqwa/muta’qee, the upright conduct/behavior. Why should one limit the Quran to God’s Law only, when it is all the above?
You sometimes say the right thing but get the method wrong! You miss the point of why the Quran is a reminder!
The reminder is the Quran so remembering the Quran is reminding yourself of Allah.
Reading the Quran in a language you understand means you should remember what it says and then act upon it. You are then doing zikr.
"in prayer" = 5 times blind recitation of the same words during physical namaz does not teach you anything new= nothing new to remember = no reminder.
"otherwise" is what you should be doing, reading the Quran part of the day, early morning, middle of the day, evening, whenever you are able, so that from morning to night, your waking day, you are a 'walking Quran'. You are then in a state of taqwa.