Playing Devil's advocate - you let a LOT of time lapse between repairs and not immediately validating the work had been done properly and didn't leak again. Seems like after getting it fixed you let it sit and didn't monitor for leaks right away. I understand extenuating circumstances, but after it leaked again after the first fix I would have demanded a thorough leak test the same day on the next fix. After the second time I would have escalated and sought to have them start over. If I am reading it right, 3 years and you've only had it fixed 3 times, that's a long time between repairs.