No, adoption of Python 3 is limited by library support, not install base. Libraries need to be rewritten for Python 3 and some major ones (e.g. Django) are not yet ready. In this case, jQuery 1.9 and 2.0 will have the same API, but 2.0 will not work on older versions of IE in order to optimize for speed. Your comment about Windows XP is apt; this is akin to software dropping support for older OS versions.

Based on the rest of the Strafor emails, there's quite a high possibility that this is just made up.

Contact other researchers who work in facilities similar to yours. I'm sure you collaborate with other labs that use HPC resources. Talk to them and get some information about how they do things there.

Personnel is really the key ingredient of HPC. Find someone, hire them quickly and give them the decision of what to buy.