I've got W11 on a laptop,used almost only for admistrative stuff and accounts, I come to think that it is better to have an up-to-date Windows in case of, but for all my machines, it's definitely 10
Latest iso off the creation tool. When adding the stock boot.wim to my WDS it even hides the w10 versions. MS also document this on their site now. I suspect your custom wim is the solution, I havent got that far with wds yet being fairly new to it.