Yes, the meeting took place at his home studio but it‘s very unlikely that the demos played at that meeting were home demos. Michael mentions during his 93’ deposition that the The Girl Is Mine demo was recorded “at a studio in the Valley” before the meeting with Q, Rod and Greg took place.
The demos presented would surely have been the latest and most sonically exciting versions, not some early rough ideas (e.g. the Billie Jean 1981 home demo or the Beat It home demo). Those were done for the musicians who were to record the demos, to get an idea of what the song should sound like.
By the way, some of Rod Temperton’s songs were also played at this meeting, including Starlight and possibly Baby Be Mine. Beat It was apparently not even written at that time, though, so they got that wrong in the post. It was one of the last songs to be written and recorded, in mid-/late 1982.