This could be a disinformation/perception management journalism. However there have been many reports of Russian PMCs in Syria. Read: MOSCOW’S MERCENARIES IN SYRIA and Russian Mercenaries from PMC Wagner
Russia has recently recruited more than 600 volunteers in the occupied areas of eastern Ukrainian Donbas to take part in hostilities in Syria, Ukraine’s Border Guard Service press secretary Oleh Slobodyan told a Kyiv briefing Thursday, October 13, according to an UNIAN correspondent.
Several organized groups, the so-called volunteers, totaling some 600 people, recently left the occupied areas of Donetsk region through the section of the Ukrainian-Russian beyond [the Ukrainian government’s] control for Rostov-on-Don.