EU Wrong WTC - affect NonEU RoR ?

[simples11]

Hi,
I have posted it recently in another section, probably by mistake...sorry, just in case
I need your advice guys.
My situation is : I am - non EU, was married with my EU wife about 8.5 years, I have RC / EEA2 / up to 2019, and now we are preparing to divorce /and RoR for me, if I am lucky enough…).

Question :
Recently, accidentally I found an old letter from HMRC and began to suspect that my wife / secretly from me / gets Working Tax Credit - I'm not 100% sure that I'm right, maybe I do not understand something and just too suspicious / this is Divorce time, too much emotions…you see... /. At the moment we live separately /still marriage, of course/.

If I understand it correctly, Working Tax Credit is made on the family, in another word, if she gets it without me - then she managed it individually and indicated that she was not married ?- and this is a violation of the tax rouls? On the other hand, because I have visa restrictions and don’t have access to public funds, is it possible she still legally issued it only on herself?

My question is: If my wife is wrong and has made such a violation - could this be a reason for refusing for my RoR application??

Thank you all for your attention.