Need help on DAX

Hi,I have data as below in the second picture. I need to create a calculated column based on the values of enter_by.1,enter_by.2 and so on. The data also has a region_id column. Have a mapping table as in picture1.

Would like to create something like below based on the information I have -

if [region_id]=1 then
(if [enter_by.1]="ODB" then "ODB" else if [enter_by.2]="ODB" then "ODB" else if [enter_by.3]="ODB" then "ODB" else if [enter_by.4]="ODB" then "ODB" else if [enter_by.5]="ODB" then "ODB" else if [enter_by.6]="ODB" then "ODB" else if [enter_by.7]="ODB" then "ODB" else if [enter_by.8]="ODB" then "ODB" else if [enter_by.9]="ODB" then "ODB" else if [enter_by.10]="ODB" then "ODB" else if [enter_by.11]="ODB" then "ODB" else if [enter_by.12]="ODB" then "ODB" else if [enter_by.13]="ODB" then "ODB" else if [enter_by.14]="ODB" then "ODB" else if [enter_by.16]="ODB" then "ODB" else if [enter_by.17]="ODB" then "ODB" else if [enter_by.18]="ODB" then "ODB" else if [enter_by.19]="ODB" then "ODB" else if [enter_by.20]="ODB" then "ODB" else if [enter_by.21]="ODB" then "ODB" else if [enter_by.22]="ODB" then "ODB" else if [enter_by.23]="ODB" then "ODB" else if [enter_by.24]="ODB" then "ODB" else if [enter_by.25]="ODB" then "ODB" else if [enter_by.26]="ODB" then "ODB" else if [enter_by.27]="ODB" then "ODB" else if [enter_by.28]="ODB" then "ODB" else null)
else
if [region_id]=2 then
(if [enter_by.1]="BDB" then "BDB" else if [enter_by.2]="BDB" then "BDB" else null)
else null

Any ideas will be really helpfule. Please let me know for more clarifications.