Are you able to connect to Collaborate on a military network or on a base, please let me know. It appears that military networks have moved the goalposts again and some students can't access Collaborate from their workstation on base.
Sometimes your local IT department can make the changes that you need. In this case, they'll need to make sure that sites US-SAS.bbcollab.com / sas.elluminate.com is whitelisted on ports 80, 443, and 2187.
You might also be able to go to the Java Control Panel and use the Advanced tab to set “Perform TLS certificate revocation checks on” to “Do not check (not recommended)”. If you can't do that, talk to your IT people and see if they'll do that for you.
Please use the comments below to give any advice for those on NMCI or any military network!