It's impossible to know if Croatia would have qualified via televotes in 2013. I believe they were 10th looking at the average placing but that doesn't mean a whole lot. It's very likely that some countries (Serbia, Montenegro, Slovenia etc) put it rather high in their ranking and everybody else superlow. Having just a few high scores can shift the average but would never be enough to justify qualification.
Yes, you have a point. Nevertheless, the system that was used to determine the plebs' scores this year were the averages and not the old 12 points count. The latter, by the way, tendeth to be more beneficial to big points receivers so as you pointed out that the Croatian entry was likely one of them it is very probable it would of fared even better there. At the end of the day though it is indeed speculation and not really relevant to this matter.