Hi, Ryan,
I am not SURBL, but I run a sizeable spamtrap platform that's used by several blocklists and reputation services. I thought I'd take a look at this -- I'm awake too early on a Saturday morning.
I found nothing for the domain flexerasoftware.com or your /22, 162.244.220.0/22. MX Toolbox blacklist check shows it listed on no blacklists. The domain reputation is excellent, and I found no spamtrap hits or other signs of trouble on my platform.
I am seeing some signs of DNS oddness -- did you recently switch nameservers?
The only other thing I can think of to ask is whether this might be the wrong domain.