first thing to do is check the cas shaft. pull it off and look at it from the shaft side, spin it by hand and see if the shaft is bent at all , if it is then thats why the bracket snapped. if this is the case, find a replacement cas.
once you have the cas sorted get a small mirror and have a look into the centre of the cam to see where the half moon section (even if its broken off you can see where it was) is then align the cas so its half moon section is exactly oppostite the cams, then slide it in.
with a standard ecu the cas bolts should be roughly in the centre of the slots, which will get it running. but you need to set the timing with a light before driving.