The numbers are friction coefficients which are indeed in the "good" part of the scale. However friction tests are run infrequently (always check the time for it, its on the ATIS), the "medium" report could be from a pilot report, however to have conflicting information is somewhat weird. Normally they report three friction coefficients per runway, not two, as well.
Can't comment on the jepp pages since we use LIDO electronic maps for some time now instead of jepp tailored booklets, however from my understanding an RNAV SID (OVERLAY) is simply a SID defined by RNAV points that is an overlay to an existing conventional SID, depending on what kind of equipment is on board and noted on your ATC flightplan you will either get the RNAV or the conventional SID.