WHAT DO I DO WHEN THE MECHANIC IS WRONG?

I took my Durango in for an alignment after I just put on new inner & outer tie
rods on both sides, the shop said that they cant align it because of a bad
upper ball joint on the passengers side. Looks like im gonna now have to do
ball joints.
BUT, the mechanic had said that he is 90% sure that I put the outer tie rod in
the steering knuckle upside down! I have spent hours looking through the
internet at pictures, etc. for the tie rods on my 2000 dodge durango & they all
show the outer tie rod ball joint has the threads pointing up in the steering
knuckle, just like I did on mine. The alignment guy has to be wrong!  What do
I do?  
Though I am expecting to replace the ball joints, after they claim just the
upper passenger side ball joint is bad, if I do one im gonna do them all. But
to do this will take a lot of driving around, which concerns me, not about the
ball joints but the alignment issue. Since they didn’t align it, I am worried
what harm could that cause? Is it dangerous? Can something break? It feels
ok driving, but it always had even before the new tie rods. I didn’t even know
the inner tie rods were bad until I took it in to have a few of the lug nut studs
replaced and when up on the rack the mechanic notified me, he said only the
inner ones but I replaced both inner & outer. I have even checked a few
times for bad ball joints when doing the tie rods while up on jacks. I found no
play, only play at 9 & 3 o'clock, indicating faulty tie rods.
Again, what should I be concerned about, if anything driving my durango
being outta of alignment?
Should I get a second opinion? Would it be safe to drive it another shop?
THANK YOU