How to reconcile Aquinas' analogical view of God with God's self-revelation?

Remember that Aquinas wrote almost 1,000 years after the doctrine of the Trinity was formulated. Analogical language is not "incapable of truly grasping or describing." It is just a form of compromise between equivocal and univocal predication, both of which are inadequate to describe God. It's not even clear what you take "analogical language" to mean, for your link is broken.

Against this background, Aquinas asks how we are to interpret the divine names. He argues that they cannot be purely equivocal, for we could not then make intelligible claims about God. Nor can they be purely univocal, for God’s manner of existence and his relationship to his properties are sufficiently different from ours that the words must be used in somewhat different senses. Hence, the words we use of God must be analogical, used in different but related senses. To be more precise, it seems that such words as ‘good’ and ‘wise’ must involve a relationship to one prior reality, and they must be predicated in a prior and a posterior sense, for these are the marks of analogical terms.

-Aquinas on Analogy, Stanford Encyclopedia of Philosophy

Your question ends with the question as to whether Christian dogmas mean that "Revelation about God's nature is in the end all mystery?" Starting with that point first, I suggest that the answer is "Not really, but..."

Thomas Aquinas argued in his Summa Contra Gentiles/Against the Errors of the Infidels (1259-64) that reason and faith are compatible. Yet the mystery of God and his nature is not "all mystery" because God himself has chosen to reveal something of that mystery with words that we humans are meant to grasp.

Take the Trinity doctrine, which is dogma, and go much further back in time to the end of the second century and the start of the third. That was an era when Christians saw an urgent need to clarify concepts, even though intellectual tools cannot explain them so that they are 'demystified'. With regard to the doctrine of the Trinity, here is a shrewd observation:

"Inasmuch as the deity of Christ and the doctrine of the Trinity are embedded in the NT, although not explicitly formulated there, we must make the effort of wrestling with difficult terminology if we are not to fall an easy prey to misunderstanding or to actual heresy.

[The doctrine of the Trinity] will always remain a mystery, but thanks to Origen, it can at least be expressed in such a way that we can see wherein the mystery lies." Heresies and Orthodoxy in the History of the Church, Harold O.J. Brown, Hendrickson, 1998 pp 89 & 91

God intends for those who seek him to find something of him and the reality of being in relationship with him so that although we will never grasp the enormity of all of that this side of eternity, we will have entered in to the mystery with opened eyes and sensitized hearts, to both see and hear what God would teach us about himself. One of the most powerful means God has given to enable that is in the sending of his Son to earth, so that, in Christ, we can see the image of God. He has coupled that with inspiring certain ones to write what the Holy Spirit directs by way of explanation. (1 Corinthians 11:7; 2 Corinthians 4:4; Colossians 1:15)

The gradual revealing of God's mysteries by God was extolled by Daniel who said that God in heaven reveals mysteries (Daniel 2:22). The whole Bible is a gradual revealing of God's mysteries, and there are many. For instance, Paul wrote of the need for believers not to be ignorant of the particular mystery of God's dealings with both Jews and Gentiles, "lest ye should be wise in your own conceits." He then explains what had been kept hidden by God in centuries past. Paul is moved to doxology:

"O the depth of the riches both of the wisdom and knowledge of God! How unsearchable are his judgments, and his ways past finding out! For who hath known the mind of the Lord? Or who hath been his counsellor..." (Romans 11:25-36)

This, to me, flags up the danger of confusing our words with God's words. Aquinas was right to say that our language is incapable of truly grasping or describing God. But when God speaks and gives us his words, as recorded in the scriptures, that should be what all dogma depends upon; not our philosophizing about God's words and trying to put them into our own words. That was the danger Paul said about becoming wise in our own conceits.

Revelation about God's nature has cleared up many false ideas held about God, yet remaining mystery will remain until we are granted entrance into the presence of God in heaven. Only then will all become clear. And then we will understand why God chose to reveal only so much of himself, and why it was essential for us to stick with the words God chose to reveal matters, and not to veer off into our own philosophical words and concepts.

We should not try to reconcile our ideas with God's. We should accept God's revelation of himself as he has expressed it, knowing that only after we have humbly done that might we be granted deeper understanding of the awesome mystery of God.