2002 Chevy Blazer ZR2 Suspension question

I have a 2002 Chvy Blazer ZR2 with 36,500 miles and a 4.3 liter V6 engine. I took it to the shop under warranty because the motor on my back hatch went kaput. The shop did their vehicle analysis and told me that I needed to have my lower ball joints and idler arms replaced, so I gave them permission to do the work. When I picked up my truck I noticed that the alignment was way off and it wandered all over the road. I took it back and they told me that the shop supervisor was training a apprentice and that the bolts weren't tightened down correctly. They assured me that it had been repaired properly this time and sent me on my way. I worked from home and didn't drive for a few days but when I got back in I noticed it was doing the same thing. I took it to an independant mechanic and he told me that my steering stabilizer shock was leaking. I didn't want to take it back to the same dealership due to the previous problems and picked up the new steering stabilizer shock myself intending to have someone se do the repair even though my truck is still under warranty. It got progressively worse over the next few days and became downright dangerous, so I had no choice but to bring it back to the shop that screwed it up the first time. Again they said that the bolts weren't tightened properly and were still loose, I think they are called caster eccentric bolts. However, this time they said that there was no way that having those loose bolts which caused my truck to swerve violently all over the road could have caused my steering stabilizer shock to leak and that the problems were independant of each other, so they charged me another deductible. I find it hard to believe that this was an unfortunate coincidence and I think they took advantage of me, so before I start the formal complaint process I need to know if I have a valid complaint and if the mechanic was totally full of it or not. I was happy to donate in order to find out the answers from a non-interested third party. I thank anyone for their advice and assistance in advance.