Because the purpose clause would be subordinate to the clause with eo, just in reversed order. With eoque it can't be subordinate, only coordinate; but in that case what triggers the ut purpose clause at all? Surely not accidit.I don't understand. Why would ut tua patria huc adducatur... eo ad fores venio, lit. "so that your country be brought to... for that/because of that I come to the door" be possible and not with eoque, "so that your country... and for that/because of that I come to the door"? The only difference I see is "and".
Maybe you mean it's just not idiomatic?
Also, like I said, I've never seen, nor does L&S seem to show, any instances in the literature where eoque follows a purpose clause. But perhaps I just haven't looked hard enough...