I don't believe there is a way to avoid this but it could potentially be a bug. I would reach out to firstname.lastname@example.org so they can determine if the product is functioning as expected.
The custom view is defined as a change, or delta, from the base view. If a republication occurs, Tableau tries to determine if the delta definition still makes sense the way the republished workbook is defined. It could be so different that the delta is meaningless, and then there is nothing to be done but to discard the, now useless, custom view definition.
Assuming that the changes to the workbook are determined to be small enough that the original definition of the custom view is still meaningful, then it is maintained. I just tested this by republishing an exact copy of the original workbook (i.e. made no changes at all when republishing) and saw the custom view still appearing.
I'm not sure how much change can be tolerated during republication, or whether the situation is the same or worse, when a custom view created in one version of Tableau is used by another version.
And, of course, just because it worked for an unchanged workbook doesn't mean that there are no bugs in the way that allowable changes are determined.