'Work' and 'Heat' both refer to energy in transit. It is therfore not
proper to speak of kinetic energy being converted to work, or to heat.
(restricted technical meaning of 'heat' as a noun.)
The puck described by Ludwik, moving with KE across a rough horizontal
floor loses energy to internal forms (vibration, deformations and
'Sensible Heat' {the old technical term for energy associated with change of
temperature}). If the frictional force is known, then the energy so
transferred is calculated as the work done by that force.
The ambiguity here seems to be the TWO ways of calculating the energy
transferred as (a) the loss of KE of the object, and (b) the work done
by friction.
Work is NOT a locus of energy. Perhaps questions of the form 'How much
work is done...' should be followed by: 'and where is this energy at the end
of the process?'