If brokers trade against their clients based on chart patterns, you have to believe they will also do so on support and resistance. If we can see stuff on a chart, they can see it too.
The fact is that any legitimate broker based in a well-regulated jurisdiction will not be trading against their clients as it would contravene their "licence" to trade. What a shell company based on a Caribbean island does is another matter but what kind of nitwit would send money to such an outfit?
Chart features are not highly reliable. Those on shorter and shorter time-frames get less and less reliable. The most consistent features are long-term trends.