Cant get data to populate in VBA code from array & scripting dictionary

I don't know the answer, I've offered up the things I would look at. I did briefly read the code in the spreadsheet but did not do a full analysis.

I think an example of what you expect to happen would be very helpful.

In your example, I see you are referencing the column = to "P11D Data due back". I don't see that string in the columns.
You referenced the column multiple times with examples of strings you were looking for.
"P11D data rec'd" --I saw in column J
"P11D Data due back" - I did not see anywhere in your data
"Completed" - In column L, which was different then column J. However, your description makes me think that you think they are in the same column.