I am not sure but I think that something is wrong with the data of this broker ... you can change the broker and make backtesting on "Every tick based on real ticks" just to compare.
It is two clicks on MT5 to open demo account with the other broker - you can look at my Metatrader for example:
MT5:
When I do strategy tester on MT5 using "Every tick based on real ticks"
I get many "Real Ticks Discarded", "Price Mismatch" and "Minutes Bars Absent" errors.
How to fix this?