CMB2-grid group classes not working

[Sebaortiz]

Hi!
I have a CMB2 Group and want to use Grid with class for the group fields but it shows me an error

Code for grid

$cmb2Grid = new \Cmb2Grid\Grid\Cmb2Grid($cmb_options);
$cmb2GroupGrid = $cmb2Grid->addCmb2GroupGrid($group_field_id);
$row           = $cmb2GroupGrid->addRow();
$row->addColumns(array(array($field1, 'class' => 'col-md-6'), array($field2, 'class' => 'col-md-6')));
$row = $cmb2Grid->addRow();
$row->addColumns(array($cmb2GroupGrid));

ERROR:
Argument 1 passed to Cmb2Grid\Grid\Group\GroupRow::openGroupRow() must be an instance of CMB2_Field, boolean given, called in C:\htdocs\site\wp-content\plugins\grid\Grid\Group\GroupRow.php on line 60 and defined in C:\htdocs\site\wp-content\plugins\grid\Grid\Group\GroupRow.php on line 47

Can someone please tell me what's wrong and what is the right way to do it?

Waiting for your reply...

[mathz]

Seems like eklingen88 have a solution for this: #42

[pablo-sg-pacheco]

Will merge it then,
Thanks

[mathz]

I've really not tested it enough to say that it really works. I only wanted to inform others with similar problems that there may be a solution