The reports came two days after IS abducted the cement workers and contractors from their workplace in Dumeir, just northeast of the capital, after a surprise attack on government forces.
The Britain-based Syrian Observatory for Human Rights said all those abducted have been released except for 30 people who were guards at the cement factory. It added that the fate of the 30 is unknown.
The Druze, a 10th century offshoot of Shiite Islam, made up about 5 per cent of Syria's pre-war population of 23 million people. Lebanon and Israel also have large Druze communities.
IS, a Sunni Muslim extremist group, considers all Shiites to be heretics deserving death.
Aamaq also released a video from inside al-Badia Cement Company in Dumeir, about 28 miles (45 kilometres) northeast of Damascus, showing trucks and bulldozers in the sprawling facility. Some fighters could be seen inside.
"I will remain a thorn in your throat and my happiest day will be when I get martyred," al-Mheisny said in the video.
The militant was wounded by a Russian airstrike in December in Latakia province.
A Saudi citizen, al-Mheisny had been fighting in northern Syria for months, serving both as a senior religious and military commander with the al-Qaida branch, known as the Nusra Front.
