If you look up urge in the Cambridge Dictionary, you will see various possible usages.
When urge has an object, the object is the person or group that you are trying to persuade, for example:
The managers urged the union leaders to reconsider the strike.
This means that usage of urge in the second sentence is incorrect, because the object in the second sentence is it, not the people.
It is possible to use for followed by a noun phrase:
The lawyer urged for leniency for his clients.
The first sentence is therefore valid up until for. There is, however a problem with the rest of the sentence: you can't say "taken the fact that". You can easily fix this by saying "taken as fact that".
The sentence is still difficult because the latter part is in passive voice. It would read better if you used active voice- "take it as fact", which aligns closely with the stock phrase "take it as read". This would make it more readable, and also make the preposition unnecessary.
This would suggest both that the senator was trying to persuade people that your father was a liar, and also that he didn't want them to check whether or not it was true.
Note that one of the uses of present simple is to talk about "something that is always true"... unless you believe that your father was, and still is, a liar, it might be better to use simple past was rather than simple present is.
The senator urged [whoever] to take it as fact that my father was a liar.
The senator urged to take it as fact that my father was a liar.