Seems like you had some flags you didn't even know about looking through the questions they asked.
When calling them use 800-947-1444 and hit 0 to speak with someone instead of dealing with the automated system lookup that doesn't work most of the time.
I still don't see why you needed the secured card in the first place based on the info provided in the previous thread. I'm guessing it's more of a challenge card based on the previous denials.
Their security is a bit wonky to say the least when it comes to some of the questions they ask but, being thorough is important with all of the data breaches in the past few years.
Their big ticket issues are usually new accounts / inquiries. If you can abstain from apps for 6-12 months things are a bit easier. I got auto denied for 2 apps with them early 2018 and called them up and got a manual review for approval 1K/ea and called them again to ask fror 25K/ea and they countered with 10K/ea. Nothing is set in stone with them though they have been more stringent in 2019 with their policies.