Hi, jumping in here as I also have the same issue since start of July,
Connecting to PayPal Express/Pro Server ... Error 28: Connection timed out after 5000 milliseconds
Connecting to PayPal TLSTest Server ... Error 51: SSL: no alternative certificate subject name matches target host name 'tlstest.paypal.com'

Apart from hosting issues, I'm wondering if this has got anything to do with Paypal's NVP deprecation to REST?