Greene has been one of Trump's biggest loyalists, and the reason she supported McCarthy so vehemently was because Trump originally wanted that, when he thought McCarthy would always bend to his will. McCarthy signed his death certificate with Trump when he refused to tank the debt ceiling, and used Democrat votes to push it through.
Trump knew, that tanking the debt ceiling would tip America into immediate recession and possible trigger a world wide depression, and he believed even if he was the one responsible for pushing it, that it is always the sitting POTUS who gets the blame and boot when people are hurting. So Trump was fully willing to sacrifice the American people and economy and world wide one, to try and get back to power.
So Kevin had to go as he had two loyalties, and his rich donors desire to not see America tanked, and thus them lose a ton of money, won out over Trump and Trump could not have that. Especially when Trump may NEED the HOuse Speaker to defy rules and laws in his second insurrection attempt, and not side with law and order and the Constitution and donor desires for stability.
So as Kevin was pushed to the dumpster, and replaced by an absolutist loyalist, Greene, being loyal to Kevin, got caught in the crossfire and is currently on the outs with that group. As she is still absolutely loyal to Trump, he will still use her, but she is more on the sidelines just being a useful idiot (never has a term been more apt) than in the core group, now.