Dynamic lighting gives my players a pure black screen.

I'm running Tomb of Annihilation and I can't use FoW or Dynamic Lighting. If I take the players to a map with DL or FoW on, they see only a black screen. I can see them, they all (or most) have dark vision. I've even tried update on drop. I can see/move the tokens, and the FoW clears correctly from the DM side. The player side, they see nothing but a black box. Tech wise, we're running 2PCs, one DM and one to a larger display (one player controls all pc tokens). I'd love to get this worked out, it'd be really great for the upcoming dungeon crawls

did you set all thier tokens to have sight? light? etc?

Other things to check: Fog of War is off. (Advanced Fog of War is different) Tokens are on the Object layer Tokens represent a character the players can control, or the token is directly controllable by the players.  Players are on the correct page (ribbon or party split)

I will try all of these things, thank you. Nearly all of my players have dark or low light vision and as a pro member, i'd like to see it used. it's neat, in that I can see it.