That's the kind of response I'd expect. Based on what I've read here and elsewhere, I think the T30 I got is probably okay. I'm testing it mainly for my own peace of mind before storing it long-term.
The COA they originally provided seemed suspicious. Like with most orders from overseas, the vials didn't have labels, only a sticker saying "Tirz 30" to tell them apart from other things I ordered. Nicely labeled vials with matching COAs from the US cost 3-10x more. Even with testing, it's still a good deal if you buy more than one.