Hmm. During your cleanse step, did you take any "keep only" actions?
The cleanse step added a filter (exclude values) on a different field. I did try removing the cleanse step altogether thinking that may had been the source of the issue, no help. The new field is still not showing up in subsequent steps.
I ran a test building two simple excel files. One contained 3 columns and one 4 columns. I built a Prep flow based on the 3 column file, saved and closed. Then I reopened and switched the source to the 4 column file. Everything updated correctly. All 4 columns show up in every step.
The original excel file has approx 100k rows by 60 columns (...then 61 columns). Not sure why source switching works with small files versus large files but for now I am done using Prep for this particular application.
Tableau please fix this software!
I have a similar problem perhaps.
A field fails to appear in Steps but is in the Source view.
This field was added, with others, after the Tableau Prep workflow was first set up.
The other fields, added after the initial setup, appear, except for this one.
Rebuilding the workflow from scratch is not, as one might surmise, an appealing option.