Okay… I think the way you put these scriptures together was accurate and I agree with you. One side note: the word KEY in Isaiah is in a singular form but nonetheless a reference to Christ.
Luke’s narrative where Christ said the Pharisees had the KEY of knowledge, only supports the idea that whether it is KEY or KEYS, it is a metaphor to explain the unlocking of doors, as stated in Isaiah 22. It is an expression.
I think we both can agree that it was an unlocking of kingdom authority to Peter. Well and good.
But our discussion must go beyond this. Was it an unlocking of authority exclusively to Peter, as mentioned earlier? If so, on what scriptural bases found in the immediate context? Peter was singled out, only because he was the only one, at the time, who answered correctly. Therefore Jesus directly rewarded him with His statement.
Peter could bind and loose, but so could the others. Can we find another N.T. witness who records or repeats these exact same particulars? No. There is no “upon the mouth of two or three…”
Peter answered the question correctly “who do you say I am?” and Jesus rewarded his answer with a declaration, You are Petros,=,masculine, (and/but) upon this Petra (=feminine gender) I will build MY CHURCH… the word “Petra” here cannot refer to a person (Peter or Christ) but to the declaration of Christ’ deity that Peter had just uttered.
So, verse 19 needs to read like this for your point to stand,
"And I will give you ALONE the keys of the kingdom of heaven… "
or… "I will give you (primarily) the keys of the kingdom… Or…
“I will give you only the keys of the kingdom…”
But Jesus made many statements about entering and possessing the kingdom of God not just to Peter, but to all of His disciples.
for instance. “to YOU (all of them) it has been given to know the mysteries of the kingdom of God but to the rest it is given in parables…” Luke 8:10.
“Do not fear, little flock, for it is your Father’s good pleasure to give YOU (all of them) the kingdom.” Luke 12:32
Was Peter the only one who could open this kingdom to everyone else? … that would be crazy. Peter was one man. If these keys were to open “kingdom knowledge” as what we see suggested in Luke’s narrative, then, they all were the direct recipients of Christ’s teaching, and therefore all obtained His understanding and authority when the Holy Spirit gave it.
“he opened their minds and they understood the scriptures…”
The special class of disciple found in Peter is not found in the narrative itself, only in traditions that came years later.
By His Grace,