I just ran into the same thing, with #$%@&*#@ poor quality machining on parts a customer brought in trying to save money on roller rockers!!! I reordered and had to wait! The dilemma you face is reordering and taking the chance on more bad machine work or taking the chance and running what you have! Being impatient is no reason to run substandard parts!!! Reorder and complain strongly to your supplier!! A valve train is no place to take short cuts or Micky Mouse around with "do you think I can"
Reorder the studs that the threads were cut and new locks & nuts that did the cutting!!! Sounds like the new Chinese, ETC quality hit you right in the kisser! Sorry it happened to you! But there has to be the 1 in a thousand !!! Murffy's LAW !!! This time it was you!