Replace #N/A with prior available values on a 2D running array with ONE "spill" formula

Below is a small sample from close market prices for 3 stock tickers using the STOCKHISTORY function:
Data.png
I realized that when no data is available for a particular stock, it then returns the #N/A error.

The problem for me is that it screws up my day-to-day % variance calculation, among other things, so I want to replace those #N/A's with the last available trading day's price, like the screenshot below:
Goal.png
But here's the catch: only a single-cell "spill" formula will work for me. On the above screenshot, it needs to be a formula on cell "AQ2" that "spills" the values down and across, the same way the STOCKHISTORY function works.

Since I don't know a way to make the STOCKHISTORY function do that #N/A replacement job in and of itself, albeit it would be GREAT if it could, I had to find a workaround to make that happen for me.

So I did a couple of calculation steps in order to get the row numbers array that would serve as input to the final INDEX function, and managed to get to a 1D "spill" solution for each of the 3 individual tickers columns on that example, as shown below (I just don't know how to trick those 3 yellow-shaded validation arrays into one consolidated formula without returning error):
1D_Spill_Row_Num.png
The couple areas highlighted in red indicate the rectified row numbers that will serve as replacements for the #N/A's that have prior values to be used on their places.
However the formula

Formula:

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only treats each column individually, and that's the piece that I'm missing to get to my final goal...
... which is the formula

Formula:

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that produces the final array previously shown:
2D_Spill_NA_Repl.png

If I can get that row number formula to work down and across a 2D range, then I would be able to replace that "$AM$2:$AO$11" piece of the INDEX function with the hash reference "$AM$2#" and therefore get this baby kicking and screaming across the finish line.
2D_Spill_NA_Repl_Complete.png

Any ideas/suggestions on how to finesse that intermediate formula?

Thanks in advance...

P.S.:
As usual I also post the same question under the Microsoft Tech Community forum, which is available on the link that follows:

HTML Code: 

There are instructions at the top of the page explaining how to attach your sample workbook.

You just read my mind as I was just trying to do that since I was unable to do so during the original posting (probably because I reached a limit due to the 5 screenshots I had already attached in the message body).

I'll do that now. Thanks!

Try

=LET(z;B2:D11;se;SEQUENCE(ROWS(z));INDEX(z;MID(BYCOL(z;LAMBDA(z;CONCAT(TEXT(IFERROR(LOOKUP(se;se/ISNUMBER(z));se);"000"))));se*3-2;3);SEQUENCE(;COLUMNS(z))))