Intermediate SSL certificate on server

HI Bullrdrnm , 
you Can extract the intermediate Certificate from the ( server / domain ) Certificate itself , and you can upload it to your Bigip in the same way of uploading any certificate and Key. 
After importing it in your appliance , you can add it in clientssl profile which you are using and put it in the chain field. 

if you need to extract the intermediate certificate , Follow the below Article : 

https://support.solarwinds.com/SuccessCenter/s/article/How-to-extract-the-Root-and-intermediate-certificates-from-the-certificate-bundle?language=en_US

If you need to install it in Bigip Follow the below Articles : 

https://my.f5.com/manage/s/article/K13302

https://www.digicert.com/kb/ssl-support/f5-big-ip.htm


if this doesn't meet your needs , you can explain more your deployment , to be able to help you.