Quality and wire gauge in cable construction is of issue here.... Small cable with tiny wire gauge has to much internal resistance and drops voltage going to tablet, and you get the red "X"....... Larger gauge wire has less internal resistance there for less voltage drop there for no red "X" in charge indicator...
Also with chargers.... Samsung tablet charger puts out 5.1 volts at 2.1 amps (2100ma) anything less is not big enough to supply correct voltage and amperage to succeed in decent charge times.... Specification are there for reason, and its all about design criteria, you want to play mix and match with underrated parts, you pay consequences...
All I can suggest is you try extension cable, if you do not get red "X" when powered up tablet with charge cable connected you are probably good to go....
I have a heavy duty 3 foot extension (off web camera or something that died in past) on my note 10.1 for about 3 months now and everything is ok.... Actual cable diameter of extension is larger than Samsung supplied cord (if it matters)...
Dale