I thought I might do an end around with the keypairs-auth problem by writing the sftp routine to work by password instead:

C:\Users\tblaz\Documents\evelyn\tja\1.betsy>perl 1.betsy1.pl
...
execution was here
$VAR1 = bless( {
       
                 'my_sftp' => {
                                'password' => 'z',
                                'username' => 'y',
                                'domain' => 'x',
                                'port' => '22'
                              }
               }, 'Config::Tiny' );

values are x y z 22
password authentication not available, IO::Pty is not installed or fai
+led to load: Can't locate IO/Pty.pm in @INC (you may need to install 
+the IO::Pty module) (@INC contains: template_stuff C:\Users\tblaz\per
+l5\lib\perl5/5.30.0/MSWin32-x64-multi-thread C:\Users\tblaz\perl5\lib
+\perl5/5.30.0 C:\Users\tblaz\perl5\lib\perl5/MSWin32-x64-multi-thread
+ C:\Users\tblaz\perl5\lib\perl5 C:/Strawberry/perl/site/lib C:/Strawb
+erry/perl/vendor/lib C:/Strawberry/perl/lib) at C:\Users\tblaz\perl5\
+lib\perl5/Net/SFTP/Foreign/Backend/Unix.pm line 256.
 at template_stuff/trans1.pm line 100.

C:\Users\tblaz\Documents\evelyn\tja\1.betsy>
[download]

This is the routine that produces this output:

sub get_tiny {

  use 5.011;
  use warnings;
  use Net::SFTP::Foreign;
  use Config::Tiny;
  use Data::Dumper;

  my $ini_path = qw( C:\Users\tblaz\Documents\html_template_data\4.val
+ues.ini );
  say "ini path is $ini_path";

  say "execution was here";

  my $sub_hash = "my_sftp";
  my $Config   = Config::Tiny->new;
  $Config = Config::Tiny->read( $ini_path, 'utf8' );
  say Dumper $Config;

  # -> is optional between brackets
  my $domain   = $Config->{$sub_hash}{'domain'};
  my $username = $Config->{$sub_hash}{'username'};
  my $password = $Config->{$sub_hash}{'password'};
  my $port     = $Config->{$sub_hash}{'port'};

  #dial up the server

  say "values are $domain $username $password $port";
  my $sftp = Net::SFTP::Foreign->new(
    $domain,

    more     => '-v',
    user     => $username,
    port     => $port,
    password => $password
  ) or die "Can't connect: $!\n";
  return $sftp;
}
[download]

All those paths in @INC looked like they're jacked up, as if the forward and backward slashed are having a tug of war.(?) But what really stands out to me in this output is that it did not change one bit when I added

 more     => '-v',

On linux, this option shows you what the backend is doing with verbosity. My current working theory is that I have no back end.

In the original post, I posted output that was suggestive that I need to use MingW to create the backend. Is this indeed the case?