Seeing that Archive::Cpio::read is implemented as

sub read {
    my ($cpio, $file) = @_;
    
    my $IN;
    if (ref $file) {
    $IN = $file;
    } else {
    open($IN, '<', $file) or die "can't open $file: $!\n";
    }

    read_with_handler($cpio, $IN, sub { 
        my ($e) = @_;
    push @{$cpio->{list}}, $e;
    });
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and Archive::Cpio::remove is implemented as

sub remove {
    my ($cpio, @filenames) = @_;
    $cpio->{list} or die "can't remove from nothing\n";

    my %filenames = map { $_ => 1 } @filenames;

    @{$cpio->{list}} = grep { !$filenames{$_} } @{$cpio->{list}};
}
[download]

I would assume that there is no file test1 in your cpio archive. Maybe there is a directory name prepended? Have a look at what information Archive::Cpio actually reads from your archive, and/or what your archive actually contains.