According to the report:
they informed the ATC officer of windshear on final (based on the on-board windshear warning) and went around climbing to FL 50 (1500 m), then climbing again to FL 80 (2450 m) to hold.
This is on the first, successful, GA.
They (MAK) have this to say about the second attempt:
One of the probable causes of the go-around decision could have been the 20-knot increase of indicated speed to as much as 176 knots within 3 seconds, which might have been an indication of a windshear.
If they can discern the trim wheel motion on the CVR, they’d have certainly picked up a WS warning, so it seems reasonable to assume there wasn’t one.