Answer to this after brute forcing looking at all named values. attributes that should have been pulled from just reading in similarly to:
info=hdfinfo(file_name)
frame = hdfread(file_name, ...
'MODIS_SWATH_Type_L1B', 'Fields', 'EV_1KM_Emissive',...
'Index',{[1 1 1],[1 1 1],[16 2030 1354]});
can be found further in the main structure info.Vgroup.Vgroup(2).SDS(3).Attributes.
Not clear how i would have found that as both Matlab's HDF import tool or the HDF viewer from hdfgroup explain where these added attributes are. Though HDFimport tool can export the metadata... the code to do so is not included in the dataset impor tcommand though they are displayd in the preview section..... aggrivating but leaving this up so others who are looking to get additional attributes know how deep into the hdfinfo structure they mayhave to go.