Well, I finally found the problem...
It turns out that once I cloned the trusted.certs (deployment.user.security.trusted.certs) file into trusted.cacerts (deployment.user.security.trusted.cacerts) file, everything started working...
I do not understand what the difference is between the two stores, futhermore, in the link that I added in the question (this), it talks about the certs file for individual usage and so... it made sense to me that it should work... however, it turns out that Java thinks differently :-)
anyways... this is the answer.
thanks everyone for your collaboration, GBa.