I am guessing the reason why you may have sometimes bet on Black and Red at the same time was because the Microgaming roulette software doesn't allow you to spin the wheel without placing a bet (very annoying). And doing this allowed you to spin the wheel until a time you were ready to place a proper bet.
The casino will say you are cheating, even though you can't win anything doing this they might say you are trying to fiddle the 'comps' system. Though that is quite a ridiculous stance for the casino to take as comps are virtually worth nothing betting 1 chip on each, unless you are betting hundreds each time on both colours they might have a case.
With what you have said they have told you so far. It seems to me they have lied and tried to twist the truth to make you out to be some kind of fraudster. I would say you have good grounds for a PAB. Disapointing that they have acted in this manner up to now.
This is a REQUIREMENT for any system that looks for a particular pattern in PAST results to ocurr that can then be used to PREDICT a series of +EV bets.
If the game is truly random, there is absolutely NO advantage in doing this, except for the CASINO. Any short term gains that make it LOOK like the system works are simply down to chance, and do NOT prove that the system actually works.
If FL REALLY believe that systems like this DO work, they shouldn't be running a casino, and MGS have some serious questions to answer about how "random" their RNG input REALLY is.
It looks like there ARE "patterns" that can be observed by spinning the wheel with hedged bets, and then placing a strategic bet at the right time in the sequence.
There have been MANY posts about these "predictive patterns", and even I have seen what appear to be patterns that give a clue as to how "hot" or "cold" the game is, and they do seem to work sometimes, even though the higher brain tells me this is "all in my mind", and it is nothing more than my brain interpreting random outcomes as some kind of predictive pattern.
The commonest is the thought that getting ONE scatter, and never two, over many spins is a PREDICTOR that the slot is "cold", and will NOT give a bonus round. Frequent pairs of scatters is the opposite, the slot is "hot", and about to give a sequence of closely spaced bonus rounds, one of which will retrigger. I have seen this, and I selectively remember the successes, and the failures also, when I have used my HIGHER brain to tell me the slot is NOT "cold" because of PAST infrequency of scatters.
Given that there is NO actual definition of "irregular play", this idea can be used to confiscate ANY winnings where the casino just can't believe a winning streak is pure luck.
This has happened before, with MiniVegas in 2006, where players who played slots with NO bonuses had their winnings confiscated for "ilegitimate play". It turned out that the software itself was COMPROMISED, because MGS had "screwed up big time" when rolling out an update, leaving TWO slot games vulnerable to a simple, bonus free, +EV opportunity.
Maybe they have "screwed up" AGAIN, and the roulette game being used HAS been given a "bug" that makes it possible to decipher "patterns" that can be used predictively. If so, there is NO WAY this will EVER be ADMITTED, not even in a PAB or to eCogra. MiniVegas never admitted to the exploit, and neither did MGS, they just paid up unless they had a more traditional excuse, such as fraud or multiple accounts. I believe FL were also involved in this, and this could explain their current FEAR that the roulette game IS compromised, and that some systems DO work on it.