ArrayToExcel | Create Excel from Array | Data Visualization library

I know that I am pretty confused about arrays and strings and have tried a bunch of things but I am still stumped. I have groups of data that I am pulling into various arrays. For example I have site locations coming from one source. Numerous cores can be at a single location. The cores can have multiple depths. So I am pulling all this data together in various ways and pushing it out into a single excel file for each core. I create a filename based on location id and core name and year the core was sampled. So it might look like ‘ID_14_CORE_Bu-2-MT-1991.xlsx’ and I am storing it to use with a xlswrite statement in a variable called “filename.” This is all working fine. But now I want to keep track of what files I have created and when I created them in another EXCEL file. So I was trying to store the location, filename and the date it was processed into some sort of array so that I can use the xlswrite statement to push it all out after I have processed all the locations/cores/layers that might occur in the original input files.
As I start the program and look in the original input files I can figure out how many cores I have so I wanted to create some sort of array to hold the location, filename and the date together. I have tried to use a cell array (a = cell(numcores,3)) but that does not seem to work. I think I am understanding that the filename is actually a string array so each of the letters is trying to be assigned to a separate cell instead of just the cell in the second column.

I also have had problems trying to push the three values out to the summary EXCEL file as each core is being processed but MATLAB tends to treat single dimensional arrays as a row rather than a column so I am kind of confused there.

Below is what I want an array to end up like…but since I am developing the filename on the fly this seems to be more challenging.