My (untested) theory:

Having two separate forms means that when the user clicks on the upper submit button, the SPCtext field is not submitted (because it's not part of that form). So  $query->param('SPCtext') is blank.

Could you expand on I tried having the textarea inside the first form but then the Field values don't exist until after the 'click'. - I'm not with you.

hth,
andy.