GERMANY: Sharia Law Applied to Child Bride Case in Bavaria. Sign of things to come in the West?

Recently, a Family court in Bavaria Germany ruled that a 15 year old who had wed a 21 year old when she was still only 14 years old, is legally married. Her Syrian Sharia marriage was given full faith and credit by the German court even though it is totally illegal in Germany for a girl younger than 18 to marry. The local authorities had attempted a sort of forced divorce of the couple claiming that the girl was too young to understand what it meant to be a wife. The judge in the case held that since the marriage was legal in Syria where it was entered into, it would be legal also in Germany.  But it was no easy decision. There was a lot of hand wringing because while the society and legal scholars were up in arms about it, both the husband and wife protested the attempt to divorce them: To wit:

“The couple have become a real problem for the German justice system: what do you do with refugees who according to German law are far too young to get married? Should their relationship be protected, or have young girls in this situation been abused?”
The couple in question arrived in Germany in August 2015, having traveled together along the Balkan migration route through Turkey and across the sea to Greece.
In September child welfare authorities in the town of Aschaffenburg, Bavaria, separated the couple, and sent 15-year-old Alia, as is usually the case with child refugees, to live in a youth institution under the custody of the local child welfare office.
However, her 21-year-old husband Amir contested the decision in Bavaria’s Family Court. In a further sign of protest, both husband and wife boycotted German language lessons.
In court, the child welfare authorities argued that Alia is too young to be married, is not in a position to understand the full consequences of getting married, and should be subject to protection under the German constitution. They added that Amir seems older than 21, and Alia seems younger than 15.

Many in the German legal community as well as in the EU at large, where stunned by this ruling as they saw it as a direct threat that German law and German culture and societal norms were not only being infringed by Sharia law, they were being usurped.
It is an interesting phenomenon that seems to be gripping Europe which at the moment is overrun by refugees from various Islamic countries that include but are not limited to Syria, Afghanistan, Iran, Turkey and Egypt. These refugees are bringing their own cultural, religious and legal norms. As they settle in and propogate, the second and third generations then become entrenched in their new “countries” and their values and culture begins to mix with the values and culture of the new country, thus changing the country from its original “purity” to a new country that is a mixture of old and new.
Is this a sign of things to come even in the United States? And what will that mean in terms of the LAW with respect to divorce and family law? Under Sharia, child marriage is condoned and perfectly legal. Divorce can be accomplished if a man tells his wife “I divorce you” three times. A man is allowed to have multiple wives. Etcetera. Will a mix of Sharia Law with Western law and culture change divorce and family law as we know it? And will the change be for the better or for the worse?