Using old iPad for Apex Fusion

[Quiverfull]

Trying to use an old iPad (iOS 9.3.5) (mounted to wall near tank) to continuously run the fusion app for my systems. When I try to login via the Fusion app I have on the iPad, I get a certificate error for the apex fusion.com server. I suspect it is because of the older iOS that i am having problems as I have no problem on my newer hardware. Any suggestions?

 

[crawling junk]

looks like it, I have 5 old ipads that i cant even download fusion onto