You just read that backwards, but for you that's normal.
There are at least two ways to interpret the relevant part of your response. One way is to note that Federal law does not prevent free riders, but it makes free riding less damaging towards unions. If that law were not in effect, federal law would be closer to the libertarian position. The libertarian position makes free riding more damaging towards unions, which is why unions and rational people do not think libertarians are "friendly" to unions. At best, libertarians are not antagonistic towards unions, which is not the same as "friendly".
The other way to interpret your response is that the current laws makes unions a problem. But that is not a union friendly view, but anti-union view.
If you have an alternative interpretation of your position that is consistent with the claim that libertarians have a "friendly" position towards unions. it would help your case to spell it out.
I started by describing the way it is right now. Like it or not, the current law is the current law.
Under current law, if a business has a union, then all employees in the class represented by the union are represented by the union. Suppose there were 75 employees in the group and 50 of them were in the union. Therefore the additional 25 are represented whether they want it nor not. That is current law. That's also why we have a "free rider" problem.
Suppose one of those 25 goes to the boss and says "hey boss, I'm not in the union, let's hammer out our own agreement separate from that in the union. That way I'm no longer a free rider." The boss can only say "if I do that the union will have me in front of the government before the ink is dry on our agreement and I will lose." That's the way it is, whether I like it or not, whether you like it or not."
Suppose those 25 get together and say "hey, we don't like that union, let us form our own separate union." The separate union will be disbanded by the primary union because federal law won't allow two unions for one group of employees. There could be a separate union in that business for a separate group of employees, but not for the same group of employees. That's the way it is, whether I like it or not, whether you like it or not.
That is clearly what I meant. Only a deliberate misreading can produce any other readings of what I wrote. I'm describing the way things are, whether I like it or not, whether you like it or not.
Now if you want my opinion, which was also in there, you can find it. I said that the law preventing separate negotiation with non-members was a problem. I didn't say it was good, I didn't come out in favor of government restricting freedom of contract. I said that the law restricting freedom of contract was a bad thing. That is clearly what I meant. Only a deliberate misreading can produce any other readings of what I wrote.