I notice the captchas myself when looking for videos to download on pornhub. JD hasn't indicated anything about them to my knowledge.
What's a limited test log? I just made a short and sweet log of it where it's working at first and then it stops. I'm pretty sure it's a captcha issue at this point...

23.01.18 18.58.03 <--> 23.01.18 19.03.31 jdlog://2530354433151/

Edit: Also just to reiterate JD hasn't asked me to solve these captchas which is what I have experienced (without issue) with other hosters in the past