Lotus Notes 8.5.3 on Sierra

I have to use Lotus Notes 8.5.3 for work (terrible software, I know), but when I updated to Sierra recently, I received this message when I attempted to open:

"More Info" led me to this page, prompting me to download Java for OS X 2015-001. Keep in mind that it states it is only supported by OS X 10.11 El Capitan and earlier. When I attempt to install, I receive this error message:

So, now I can't access my Lotus Notes mailboxes (we have no support for webmail). I have no idea what to do!