You can always look in the repositories and see what is available for other versions of OM Lx. In the case of nodjs 14.15.4 is in Cooker so that is going to be the most recent version available.
Next go to #oenmandriva-cooker at Freenode IRC and ask developers. Or alternatively you can file a feature request on our issue tracker following instructions here. Going on IRC is likely to produce a faster answer. However even on IRC people need to be patient. Post your question and anything else you wish to say and someone will answer when they can. We are a small group as most of you know and even our devs sleep sometimes.