I did a different test where I solidly mounted a point just a millimeter or so inside the chain at the sprocket. Spin the wheel and check to see if the sprocket is round - which it is. There's maybe a millimeter of deviation. Conclusion - it's a poorly manufactured D.I.D. chain.
If you have even 0.5mm deviation, it is too much, it is NOT the chain that is causing the issue.
I work in the bike industry at a major distriubutor (different brand chain) and i can tell you now, it aint the chain, we have people blaming the chain with the same symptoms and causal effects as yours, and it is an issue with the sprocket. Even though we dont sell DID, i can vouch for them being an excellent chain.
Test this in a different way. Rotate the wheel until the chain is loose, then tighten the chain adjuster by 1mm and see how much the chain lifts.
As i have also said previously, reposition the sprocket, as long as it has some clearance between its centre hole and the hub....
The ONLY thing that MIGHT be wrong with the chain is if the joiner link has been overtightened when installing, test the motion of that joint against the remainder of the chain, that is the only way the chain can cause any issue, as it will not straighten out after it leaves the sprockets, effectively shortening the chain.
IF this is the case, it is not the chains that is at fault, it is the installation, and yes, you can overtighten it if you go just that bit too far.
I also mentioned, have you used new sprockets ?