Just curious. Have you tried the extension called Chessconnect others have reported?
https://www.chess.com/forum/view/chess-equipment/solution-for-dgt-board-on-chess-com
https://www.chess.com/forum/view/chess-equipment/solution-for-dgt-board-on-chess-com
I have a beautiful DGT Bluetooth Walnut e-board. It is a board you commonly see at top tournaments - currently being used in the Candidates, and is routinely used for World Championship matches (you can see it in the picture below being used for the last Women's World Championship). The chess.com "DGT" button for live gameplay doesn't work to connect this board (it only works for the Pegasus). Many people have alerted chess.com to this issue for years, and it has not been fixed. This must be reasonably simple to do, as Lichess and Acid Ape connect these boards very well for live gameplay, with excellent move announcements. Why hasn't chess.com done the same?
My Diamond membership expires on 28 July. If I can't use my beautiful tournament board to play on chess.com by then, I will not renew it and I will play my live games on Lichess.