Therefore two issues remain. 1. Does the aircraft's AOM preclude this sort of operation and 2. Is it economically worthwhile to do so?
If the AOM permits it, and it's economically worthwhile, then the matter doesn't end. There are third and fourth issues, the fourth is perhaps the most important one:
Third, what do flight operations want? Tanking a lot inbound to a hub, for example, can be unhelpful if the deployment of airframes for the next day's operation has not been finalised; this is most true in a mixed long/medium/short haul operation. So, a brief call to ops is in order.
Fourth, the commander must decide whether, if there are additional hazards or elevated levels of risk from tanking, he is willing to accept them. If tanking onto a contaminated runway is permitted, then a crosswind might advise that adding to the landing weight is unwise whereas a reliably-forecast wind straight down the strip would not.
For me the decider on the 'contaminated' question is that contaminated figures are only ever 'best guess'; they provide none of the certainty that dry, damp, and wet do. I would not tank onto a contaminated runway for that reason alone.
Finally, I can't help having a feeling that the OP may be being asked to run before he can walk with confidence. It sounds like a somewhat obtuse question that's been posed; certainly clarification from the instructor would be in order, best in the form of: 'Here's your flight plan, here is the weather, here are the NOTAMs... What will you do?'. And anyhow, this is the sort of decision which will ultimately be made by an experienced commander, so asking someone who hasn't had the benefit of line flying experience is a little tough. Well done to the OP for coming here and asking in a good professional style.