Escape from captivity

Last month I came across some information concerning yet another commentary on Avot that I had not previously encountered. Its source is Israel Mizrachi (Jewish Press, Features on the Jewish World, here):

Rabbi David Hazan (d. 1748) was a noted rabbi and kabbalist, author of several books and founder of a prominent Hebrew printing press in Izmir (Smyrna), Turkey. ... I was able to obtain one of the books he authored, titled David Bametzudah (translated as “David in the Fortress”), being a commentary on Pirkei Avot (Ethics of the Fathers) and printed in Salonica, Greece in 1748. The title page tells of the interesting background to the writing of this work and the travails of the author that led to it.

In translation, this background praises the grace of God and continues as follows:

“While I was visiting the city of Vienna, being that it is their custom to require passports of every visitor, I had in my possession an authentic passport. An evil man spoke slander about someone with the name David and said before the government that he was a spy. Despite our father’s names being different they accused me of being a spy and locked me in a prison on the holiday of Pesach. Since I was of ill health, the Jewish community sent a doctor to request that I be sent to a hospital under surveillance. May God repay them for their kindness. They instructed the doctor to care for me and paid for all the expenses. I was there from Pesach until Shavuot. I requested from the community leaders to send me the Midrash Shmuel on Pirkei Avot and Ein Yaakov (on the Aggadic portions of the Talmud), and within a short time I had written this commentary on Pirkei Avot. The very day that I completed the writing of this work, I received a pardon and was released…”

According to the online entry in the Jewish Encyclopaedia, the author's full name is David ben Chaim ben Joseph Ḥazan. He lived in Jerusalem about the middle of the eighteenth century. In addition to this commentary on Avot he wrote Ḥozeh David (commentary on the Psalms, Amsterdam 1724), Ḳohelet ben David (on Ecclesiastes, Salonica, also apparently 1748); and Agan haSahar (on Proverbs, Salonica 1749).

I have not seen this work and have never even come across any reference to it in the works of others. I'm curious to know whether it is a yalkut upon a yalkut, taking extracts from Midrash Shmuel and refreshing them for contemporary readers, and whether it has a kabbalistic flavour. If any reader can enlighten me, I shall be grateful. 

Meanwhile, noting that Rabbi Hazan was pardoned and released from prison on the day he completed his work, I wonder whether it ever occurred to him that, had he written a shorter commentary, he might have been released sooner.