I did try precaching on map start, didn't change anything. I made some progress though. It was the model. materials/sprites/laserbeam.vmt works where materials/effects/laser1.vmt did not.
So now I have a good beam between the players but there is another problem. You can only see it if you are facing a certain direction and are very close to it. So you need be looking down the beam (only works 1 way) and if you turn your eyes either direction it fades until fully transparent. I used this material with TE_SetupBeamPoints and it worked fine so its not that.
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