There's no multiboard view for custom players' tv. It might be an interesting feature, perhaps integrated into the Study feature or if lichess.org/tv
was customizable, both of which have multiboard view already. You can make a feature request in the Feedback Forum:lichess.org/forum/lichess-feedback
What you can do right now is just open the games in separate windows, reduce the board and site size, and arrange them so that they're all visible. On Windows, for example, you can arange them in this way automatically, by right-clicking the taskbar and choosing "Show windows side by side"
Also Win+Tab on Win10 could get you a similar result:
This too will show live windows.