How do you use Lookups with external users - primarily, how do you hide other columns?

I use a lot of lookups. I’m sure many of you do. For our needs, we have a lot of users use Coda who are not tech savvy - but also like to click around; and some details are confidential… So we absolutely have to avoid showing too many columns, particularly for Lookups.

In my case, I am using Lookups as a dropdown for requesters to select a location that is from a Lookup table. I only want requesters to use that column as a “Select List”. On my end, I will still use the data as a lookup as I will refer back to it for other things. What’s the most convenient way to do this? My current method is to create another “select list” column, create options by writing a formula for the Lookup table’s column name, then the “real” column will be a formula based on this select list column. I find that cumbersome. I tried using the base table as the lookup but hiding all the other columns, but it’s weird that there’s the hover over.

This might dwell into the “suggestions/feedback” arena, but I feel it would be very useful to make it easier to hide data and/or not show any data at all when the cursor hovers over.

So… TLDR, how do you use lookups with external users?