I'm trying to create a bracket for video game tournaments and I'm having trouble with some of the functionality I want it to have.

Right now, I have cells B7 and B9 that will pull player names from another check in sheet. I have another cell, D8, that I would like to have a drop down list in containing the contents of B7 and B9. Everything I see online says to use Data Validation, but apparently that tool can't make a list using cells that aren't next to each other, so that won't work. How else can I tell excel how to populate this list? It is vital that the cells be apart from each other because the visual formatting is necessary for displaying the bracket on a projector so that the players can see their match assignments.

In addition, I would like to have another drop down menu in another cell with a list of valid bracket sizes (4, 8, 16, 32, etc.), and have the cells of the sheet either be visible or invisible depending on how many max players can enter. In other words, if columns B, D, F, and H correspond to the number of rounds it will take to finish the tournament (3, 2, 1, and 0, respectively), I would like the sheet to display only the cells necessary for the tournament, pull player names into the left most cells needed from another worksheet used for sign ups, and auto populate all of the columns to the right of the column for first round with drop down lists for the players who could have won that match in the previous round.