Using AWK or SED to find & replace in doc B from CSV A

@rtwolfe94022 wow! and you consider using sed inside awk piped to while read with the eval a worth solution?
I'd suggest you read-up on "best practices" of shell scripting. This approach is definitely NOT a "best practice" of nesting tools when the operation can be performed by either one.

Take a look here, here and here among other google-able hits for sed inside awk.

I'd also suggest formatting your code/data samples with the the proper markdown code tags.