Not all theologians believe that the Gospels are that old.
We have to be aware of modernistic influences in theology ( nowadays modernism is mainstream theology)
You say : reported speech . yes but inerrantly reported then.
For the rest I agree with you , the magisterium explains the faith authoritative. Christ teached the apostles . They preached it . then also some of it was written down , under inspiration of the Holy Spirit. inerrant .
the tradition is the unwritten word of God (the teaching of the apostles)
the magisterium is the teaching authority Christ gave to his apostels .
The Holy Spirit is the helper , for the whole church, but ultimately the Bisschops /pope decide . But always building on/ explaining further on that what is already revealed .
Not only the NT. contains revelation . Also the tradition , but always in accordance with that which is already teached .

They are not miljonairs ! Father Amorth+ , the late chief exorcist from the Vatican called Medjugorje a fortress against Satan.
I have been there 10 times , and it is authentic , no doubt.
It is the biggest confessional of the world. The pelgrims pray the rosary constantly or go on the hill praying the way of the cross. Adoration now almost 24/7 . It is real , believe me .
Father Amorth :
Father Gabriele Amorth on the Sin of Ignoring Medjugorje

The DDF didnt condemn the apparition.
They didnt investigate it, they "just" did something bureaucratically.
They said that a document of 50 years ago is still valid ...
The notification of 1974 .
Which is already long outdated. By the same discastery, a few times.
They dont seem to know. namely in 1996 cardinal Ratzinger ( chief of the DDF ) gave permission for the release of the devotion , and added ; the final approval we leave for later date .
The later date was then 2002 when the bisschop of Amsterdam did approve it.
Already in the eighties , ( 1983) the DDF, then congregation , asked the bisschop to see if he could release the devotion .
This decision now is a bureaucratic decision by a few people there who dont know the history , they never investigated anything , just hold on to a outdated notification .

it is impossible that Medjugorje is false.
All those people ( the 6 seeers) cant have been lying for more that 40 years.
They would have been totally schizophrenic to do that .
Furthermore : many million people going there praying the rosary , confessing, etc.
Some of the seeers benifit from the pelgrims ( everybody in Medjugorje benefit a lot from the pelgrims )
But is that wrong?
It was an extremely poor village , like mediëval poor .

We may use our own common sense , given by God.
Although we have to be obedient to the magisterium with regard to the deposit of the faith, this doesnt mean a serviel obedience to everything.
An apparition doesnt belong to the deposit of the faith, unless... something is being said that goes against the faith.
That would be heretical, but in Amsterdam that wasnt the case . Neither the first bishop (Huibers) who investigated the apparition, and came to a "non constat", nor, later the CDF (DDF now) made such an allegations.
The fifth dogma which is being asked but is not an heresy ( although not everybody think it is right) , but JP II talked about it and other popes implicitly and explicitly ( Pius XI) .
Also in the supplementary documents of VAT II it is mentioned (not in the official documents promulgated ) but you can find it in the "acts of the council" ; they say: "coredemptrix is verissima" ( absolutely true), and give a lot of reverences .
So in 1974 the CDF comfirmed the position of bishop of Haarlem-Amsterdam. But they didnt investigate it themselves , they just read the file.
Paul VI approved of the publication of that decision , he didnt investigate it himself , he didnt issue a papel decree , nor a moto proprio. He just signed o.k. for official publication (in osservatore romana). Somehow the CDF of today construes it as some papel decree , but it wasnt that, ( then that decree would have been published and signed by the pope) but it was a very short publication of the CDF ( the notification ) .
Since the devotion kept spreading nevertheless, the CDF in 1980 decided to refer the matter back to the bishop of Amsterdam to look in to the matter again.
Finally in 1996 the bishop of Amsterdam was in Rome . spoke with Cardinal Ratziger , (em.-pope Benedikt † )and the conclusion was: lets approve the devotion . ( Always first the devotion is approved , then after some years, possibly, the total approval, this according the the : norms for apparitions).
In 2002 the bishop of Amsterdam approved the apparition fully, for which he thought he had the right , according to the "norms" .
Rome didnt object and they certainly knew.
Now, in 2021, the CDF decided that the "notification" of 1974 is stil valid.
(it has to be noted that is was probably only one or 2 persons within the CDF who decided this , not the whole of Rome)
But... the did somehow still allow the devotion !? as long as it is not alleged that Rome approved the apparition ( the only approve the devotion).
...But the notification - by which they abide- does in fact NOT allow the devotion ....
So it is one ambigious , unclear "decision" they made , a sort of bureaucratic act, which leaves everything open , decides nothing , explaines nothing. and doesnt take into account what Card. Ratziger , former prefect of the CDF has said ,unfortunately that seems not to be in their dossiers.