If you DVed and they responded, then they've a minimal definition at least for validation. Whether it is sufficient would be up to the District and Circuit courts.
If you cannot find them searching the SOS website, call the Indiana SOS and ask whether this CA is licensed in Indiana. Tell them you searching the SOS website, but you couldn't look them up.
If they cannot find them as licensed or bonded in Indiana, see if they will mail or fax you something stating this company is not licensed as a CA in Indiana. If you don't have a fax machine, call a local UPS Store or Fedex Kinkos or some similar place that has a fax where you can receive stuff.