A/N before story

Y/N L/N is a Russian Infantry Officer who has served for 5 years in the US Marine Corps prior to becoming a Russian officer. He was to support the Syrian Democractic Forces on their offensive against ISIS in the rumbled city of Aleppo, along with some US Army Green Berets, as an act of cooperation between the US and Russia. He later went MIA that day for unknown reasons and ended up in another version of Earth entirely. What will await him there?