With the zsh shell:

set -o extendedglob searchdir=/volume2 filename=list-in.txt names=( ${(f)"$(<$filename)" ) files=( $searchdir/**/(#i)(${(~j[|])names:r}).*(ND.) ) print -rC1 -- $files 

In addition to case insensitive matching enabled with (#i) here, you can also enable approximate matching. For instance (#a2) allowing matches with up to 2 errors (omissions, insertions, transposition, different character).

With the zsh shell:

set -o extendedglob searchdir=/volume2 filename=list-in.txt names=( ${(f)"$(<$filename)"} ) files=( $searchdir/**/(#i)(${(~j[|])names:r}).*(ND.) ) print -rC1 -- $files 

In addition to case insensitive matching enabled with (#i) here, you can also enable approximate matching. For instance (#a2) allowing matches with up to 2 errors (omissions, insertions, transposition, different character).

• $(<file) expands to the contents of the file. Here it's quoted to prevent IFS-spitting.
• ${(f)expansion} splits the expansion on line feeds.
• ${file:r} expands to the rootname of the file (extension removed). When applied to an array, that applies to all the elements.
• ${(j[|])array} joins the array elements with |. With ~, that | is treated as a glob operator (alternation).
• **/ matches any level of subdirectories (including 0).
• (ND.): glob qualifiers:
• Nullglob: no error if there's no match
• Dotglob: also look for hidden files
• . matches only regular files (like the -type f of find).