Your agenda has multiple occurrences of some roles. In this case, only the 1st occurrence of the role in the agenda editor has the drop-down. This is by design.
Additionally, I found that your Evaluator #2 has an extra space in the 2nd occurrence of the role. In order for the software to recognize multiple occurrences of the same role, they must be spelled *exactly* the same, including spaces, OR keywording (use of asterisks) must be used to indicate the part of the role name that should be used by the software to determine multiple occurrences of the same role.
Please refer to
support.toastmastersclubs.org/doc/item/editing-an-agenda
("Repeated and grouped roles")
If you get familiar with our online documentation and use the system as intended, you will find that it works just fine.