RHS,
It is clearly a course designed to introduce the single pilot to the dual crew environment so they don't (hopefully) have to spend the first 16 hours in their very expensive dash sim teaching you there's someone sitting next to you, and aircraft go quicker than 140kts.
I think that the presence of another person next to You should be covered by MCC course, which is required to start a JOC.
if we're to be pedantic a certain amount of thrust is also produced from the exhaust gases (jet enough for you?)
The same amount of thrust is leaving the exhaust pipe on a turboprop as it is leaving the exhaust of any car. Congratulations! You are now in possession of a jet car!
The energy of the gas is taken entirely (or should be, depending on the engine efficiency) by the power turbines in a turboprop. This is not the case in turbofans, where some amount of thrust is produced by the core section. The working parameters, temperatures, pressure ratios are also different for both type of engines. So, no, Dash is not enough jet for me. Like pilotchute wrote, this requirement is just to cut the number of CVs flying from applicants, regardless it makes sense for this particular position or not.