Luther Believed Mary Was Crowned Queen of Heaven?

Here's one from a discussion board in which Luther is purported to have believed Mary was "crowned Queen of Heaven" and made sure to have it "carved on his grave."

....we Catholics do believe that Mary was crowned Queen of Heaven. I respect that you don't believe it, probably because it is an event not recorded in the Bible. But Martin Luther believed it. I believe he had it carved on his grave! He expected to meet his Queen in Heaven... We Catholics believe it is part of Sacred Tradition handed down from the Apostles, and from Jesus himself. Mary likely would have MUCH rather have died for humanity than see her son die, if it were only possible, but in her humility and wisdom she certainly knew that only God can do that. She knew her place, always. In icons, she is always pointing to Jesus.

I asked for some documentation and the response was, "Just google it. Its out there." We'll see below that there's a strong dose of embellishment going on in regard to Luther's use of the phrase "Queen of Heaven" and there is blatant error in regard to what's printed on Luther's grave.

Queen of Heaven
I've previously done a detailed look at Luther's use (or lack thereof) of the title, "Queen of Heaven." Luther was against the Salve Regina and the Regina Coeli which blatantly affirm Mary's queenship.  I know of only one instance in which Luther positively uses the precise phrase "Queen of Heaven," and he does so in order to downplay the excessive Marian devotion of his day (Luther's treatment of the Magnificat, 1521 [LW 21:327-328]) He says,

It is necessary also to keep within bounds and not make too much of calling her “Queen of Heaven,” which is a true-enough name and yet does not make her a goddess who could grant gifts or render aid, as some suppose when they pray and flee to her rather than to God.

The Mary of Luther in 1521 and the Mary of 16th Century Rome are different, for in the later view, Mary is someone to pray to and flee to who grants gifts, what Luther would call, a goddess. According to Luther, by pouring more into the term "Queen of Heaven" (like the defenders of Rome do), "we can easily take away too much from God’s grace, which is a perilous thing to do and not well pleasing to her." When Luther here says "Queen of Heaven" "is a true enough name," he does not mean the same thing Rome's defenders do. If there's any agreement here between the defenders of Rome and Luther, it's only surface level.

Luther's exposition of the Magnificat was seen in his day as an attack against popular Marian piety, and is a transitional work in Luther's Mariology not entirely reflective of his later thought. In chronological order, Luther's 1521 admitting a use of "Queen of Heaven" is followed by 1522's "doing Christ a disservice" if one uses the title. Then for the rest of Luther's career, the Salve Regina and the Regina Coeli were to be avoided as blasphemous.

Luther's Grave
According to the defender of Rome on the discussion board, this rare instance of Luther downplaying the title "Queen of Heaven" becomes a lifelong deep belief provoking Luther to make sure to have it "carved on his grave" after died. I've covered this myth before. As far as I can tell, it may have been Rome's defender Peter Stravinskas who popularized it:

Let's let another defender of Rome correct Rev. Stravinskas. Tim Staples of Catholic Answers says:

Luther Was Not Buried Beneath An Image of Our Lady....  Martin Luther did retain much of his Catholic Mariology after having left the Church. But there are also not a few myths about what Luther did and taught floating about in Catholic circles. If you haven't heard this one yet, you will. It has been written about and spoken about by quite a few Catholics, and I have personally heard some very well-known apologists state it as true as well. The myth claims there to be a relief of the Coronation of the Blessed Virgin Mary with an accompanying inscription by Peter Vischer the Younger over the tomb of Martin Luther in the Wittenberg "Schlosskirche" ("Palace Church") where he is buried. "See?" The argument goes. "Luther believed in Mary assumed into heaven and crowned as Queen of Heaven and Earth!" Unfortunately, it is actually a memorial plaque for Henning Gode, the last Catholic Prior of that church, who died in 1521. Same building, but not connected to Luther.

Conclusion
Yes, if one Google's the information it is "out there," both the errors and the facts. For some of Rome's defenders, anything that remotely seems like their version of Mary becomes "Luther expected to meet his Queen in Heaven" and so should Protestants today.  All the typical attacks against Luther cease, and he becomes a staunch supporter of Mary; a leader that all contemporary Protestants should learn a great lesson in Mariology from.

Yes, Luther had a Mariology. It reflected his commitment to Christ, and stood in antithesis to popular Roman Catholic belief in the sixteenth century. Some of the Roman Catholics during Luther's day actually were suspicious of his Mariology, particularly his explanation of the Magnificat. Even later Roman apologists, some quite hostile to Luther understood this. Hartmann Grisar, commenting on Luther’s Magnificat states, “[Luther] certainly was in no mood to compose a book of piety on Mary. The result was that the book became to all intents and purposes a controversial tract, which cannot be quoted as a proof of his piety or serenity of mind during those struggles.”[Hartmann Grisar, Luther IV (London: Kegan Paul, Trench, Trubner and Co., LTD, 1915), 502].