From what I know about Arman Tsarukyan he is from a rather wealthy family and lives a well lavished lifestyle.
So when someone says that they paid him money to do something, I tend to question the source. And from what you had just stated, I would definitely do the same.
The guy doesn't need to fight for the same reasons that most in the organization have to and rely on fighting two or even three times a year.
From the sounds of it, Arman wants the easiest way to a title as possible and if it isn't on his terms he won't do it. That is all I can really say about this fighter and his current situation of trying to find a fight.
I agree with you, he is very rich. What could Islam offer to him? How much money? He has money, an additional million or two doesn't matter for him. So, it's definitely a false claim.
Do you think that he pulled out of the fight because Islam wasn't an easy fight for the title? He gave Islam the toughest time in his debut and I guess, it wouldn't be a hard fight for Arman. He was losing nothing by fighting Islam. I can't really believe if he pulled out because of back injury cause it's a common thing, you dehydrate so much during the weight cut that everything hearts because everything inside is dry. Pulling out of fight put Arman in much worse state. First of all, Dana White hates him and he won't get an easy title shot the next time and secondly, Topuria is no easy fight. I would say that Topuria is a better fighter than Islam but that's just my opinion.