Set a custom path tag for non conforming albums

I was trying to populate a custom attribute with the subpath to an album, only for albums which dont conform to a standard defined as
W:\Music\AlbumArtist(Year) Album[Disks]\Tracks ...
(where 'the albumartist' is stored 'albumartist, the')

Some albums like compilations, soundtracks, musicals don't follow the standard. I want to capture non conforming albums and their locations in a custom attribute to help with onward management.

Non conforming albums look like
W:\Music\CouldbeAnywhereanynumberofsubfolders(Might have Year) AlbumName\Mighthavedisksubfolders\files

such non conforming albums do not have albumartist in their path.

This format value action seems to work.
$if($eql(%_folderpath%,$regexp(%_folderpath%,%albumartist%,)),$regexp(%_folderpath%,W:\\Music(.)\\{1}.%album%.*,$1),)

non conforming albums have a tag populated with a subpath.

However it is unable to deal with (ie ignore) the case with album artists with a 'the', as they are stored...'albumbumartist, the'

using a previous expression / action

$regexp(%albumartist%,^The (.+),'$1, The')

...ive tried
$if($eql(%_folderpath%,$regexp(%_folderpath%,$regexp(%albumartist%,^The (.+),'$1, The'),)),$regexp(%_folderpath%,W:\\Music(.)\\{1}.%album%.*,$1),)

to no avail...any ideas please?

$if($eql(%_folderpath%,$regexp(%_folderpath%,$if($grtr($strstr(%albumartist%,The ),0),$cutLeft(%albumartist%,4),%albumartist%),)),$regexp(%_folderpath%,W:\\Music(.)\\{1}.%album%.*,$1,1),)

seems to be a workaround...

but %album% wont match if it contains () in the album....is there a workaround?