1mm worth of wear it HUGE when it comes to cams as if the cams worn by 1mm or the lifter has a 1mm dent in it then the cam is going to have gone through the hardened bit of either which will lead to it just wearing away even more the more you use it

get a cam kit that has the cam and lifters and lube in it
then get someone professional to fit it up for you
at least that way you will know what's been done and they can show you what the old cam was like and how they've run the new cam in

obviusly you seem to have done this before which may be why the cams fucked now?