I think the simple fix is good when there is just one column involved (e.g., @Column (or default logical name based on attribute name) or @ColumnTransformer( forColumn="..." ))

As you mentioned, to deal with more than one column, I think that any ambiguity can be resolved by adding the following to ColumnTransformer:

SqlFragmentAlias alias() default ""

If the alias is specified, then Hibernate should only use an alias where explicitly specified in the values provided for read="..." and {write="..."}}.