Flying South America to Africa (Morocco)

I would suggest to fly to Madrid and to take a low cost flight from Madrid to Morocco but verify how much will you have to pay for your baggage with the low cost airline you choose (in order to know the real cost of that option and to decide if it's worth it or if it would be better to fly from Madrid to Morocco with a non-low cost airline). BTW, don't forget that having two separate tickets, if you miss your second flight due to a late arrival of your first flight, you'll have to look and pay for alternatives on the spot so allow plenty of time between flights. BTW, in case you missed your flight from Madrid to Morocco, to make the route by surface transport could be cheaper than a flight purchased on the spot.

Should I expect to pay around the 2k mark?

It'll depend on your travel dates, when you book your tickets, what's your departure point in South America... but if you are flexible with your departure point in South America and you book your tickets well in advance, I think you should be able to find fares cheaper than 2k US$.

Should I fly into one of the major european cities first, rather than direct to morocco?

Yes. In fact, AFAIK, there aren't direct flights from Morocco to South America.

Should I expect to pay around the 2k mark?

Well no, not if:
Turkish airlines was by far the cheapest, at around $1100 from buenos aires to casablanca

I think $1100 is a good price for that route, which can't be a common one. But check out routings via Spain or the east coast of the US. We got flights from Bogota to New York last year for $300 on JetBlue, so if you can find a cheap flight from NY to Morocco that could be an option.

You could also try searching for flights from Sao Paulo (which offers many cheap flights from South America to other continents) to Lisbon. Condor has extremely cheap flights from South America to Frankfurt, for instance from Recife. It's probably easy to get a cheap flight from that part of Europe to Morocco too.

Thank you all for the tips! I'll check out those different airlines and departure points and compare them.

Yep I'm flexible with my departure point. My travel route will be (partially) dependent on flights/costs.

One word of warning. When it comes to cheap airlines from Spain - DON'T go with Ryanair - or Ruinair as we call it here...