2 Samuel 23:5
"For does not my house stand so with God? For he has made with me an everlasting covenant, ordered in all things and secure. For will he not cause to prosper all my help and my desire?" ESV. My emphasis.
A] "with me". With me merely as a beneficiary; unconditional upon any action or input from David.
B] "with me". with me as a participant in its being achieved. i.e. Conditional upon an action of David's. e.g. "The LORD dealt with me according to my righteousness;". 2 Samuel 22:21.
Chronologically, what king David said in 2 Samuel 22:21 must be considered first, as you have included this verse, implying that it is connected to the verse in question in the next chapter.
The twenty verses leading up to 22:21 show how David was reminiscing about previous near-disasters as verse 1 shows:
"And David spake unto the Lord the words of this song in the day that the Lord had delivered him out of the hand of all his enemies, and out of the hand of Saul." A.V.
The way the Lord dealt with him during those past difficulties caused David to rejoice and to know God as his rock, his fortress, his deliverer (vs. 2). Chapter 22 was his song of thanksgiving to God, particularly those up until Saul's death.
Chapter 23 is not this song. Verses 2 to 7 are the last words of king David. God had told him that "He that ruleth over men must be just, ruling in the fear of God", and to be like light on a cloudless morning. David then acknowledged that although it was not so with his house, yet God had made with him (king David) an everlasting covenant. Interestingly, David added that this covenant was his salvation and all his desire, even though God did not make it grow (verse 5).
In both verses (in chapters 22 and 23), David is the one with whom God is dealing. But in chapter 22 it is a looking-back at how God had wonderfully dealt with David, rewarding him by those deliverances.
In chapter 23 David is speaking of the present steadfastness of God's covenant with him, and that it is an everlasting covenant.
First, the phrase "with me" does not occur in 2 Sam 22:21 - the word is יִגְמְלֵ֥נִי = "rewarded me".
2 Sam 23:5 is a simple statement of the fact that God established the royal Davidic covenant with David and his progeny which would ultimately reach its climax with the coming of the Messiah, Jesus Christ as per Luke 1:32, 33 -
He will be great and will be called the Son of the Most High. The Lord God will give Him the throne of His father David, and He will reign over the house of Jacob forever. His kingdom will never end!”
See also Acts 13:34, John 1:49. This royal Davidic covenant, inherited and fulfilled by Jesus,
None of these could be accomplished by David and thus it was the work of God alone.
We see another example of this in the Israelite covenant where, at the initiative of God alone, God established Israel as a nation, holy to God (Ex 19:5, 6), not because they were greater and more numerous than other nations (Deut 7:1, 7, 17, 4:38) but because God made a sovereign choice to love them, Jer 31:3.
Therefore, of the OP's options, I would selected option "A".
