formula to Check if cell value matches with Dynamic Row Number.

Thank you for introducing me to the LET()Function. It works great. However I have encountered another issue that I have spent countless hours of reading and watching videos to try and solve. I am not sure how to upload my worksheet so I have condensed it down to post it here. Any help or guidance what I should research would be greatly appreciated.

As before:
1) I have two separate Sheets
a) Date of Departure, b) Date of Arrival
2) The Guest name can be on the same sheet multiple times with different Site#
3) The Guest can be on the Departure sheet and be staying longer so they appear on the Arrival sheet as well.
a) If they remain in the same Site# they are considered an "Extension"
b) If they want to stay but have to move to a new site they are considered a "Move" and my sheet needs to read "Move from Site# x to Site# y.

I have narrowed the options down to this formula:
=LET(
ar_site,INDEX($F$2:$F$201,MATCH($B2,$E$2:$E$201,0)),IFERROR(ar_site,""))

Where column
F - Index = Arrival Site#
B - Match = Departure Name
E - Match = Arrival Name

Issue:
If the Name appears multiple times my MATCH formula gives me the same row
number for each occurrence of the name and thereby the same Site# instead of the correct one. How can I get the correct row with multiple matches?

I will gladly upload my work if you cn direct me how to do so.

Thank you in advance for your help.