Yeah glide columns can’t become an array based on sequentially numbering them. Only columns that exist in the sheet. I wish you could, but it’s not an option. What you could do is create a template column that joins all the lookup columns with a comma (or any other) delimiter. Then use the split texts column to split that template column into an array.
Also gonna throw a request in here that I really wish we could access the individual array items in a Split Texts column, like we can with a sheet array. It would be an awesome way to split a formatted date column to get separate date and time values to use in separate components.