Unfortunately Holacracy is not a magic pill that means everyone will do their part. You will still need to have crucial conversations with your colleagues. The good news is that each team member has the authority and duty to speak up when they have tension.
As in any organization the best solution is likely to have a conversation about what you're expecting and what is not getting done. You will have the increase clarity of a clear role description to help that conversation. I would try to offer a clear observation then invite Jeremy to share his perspective. One phrase I really like is, "What are your next actions or projects on this accountability?"
Sometimes it is just getting clarity about what the accountabilities mean to each person. They are pretty bundled so perhaps you want to get clarity in governance if different people are interpreting role accountabilities and are expecting different things of each other that tension can quickly be solved with establishing clearer governance.
Sometimes people have too much on their plate in which case they may need help prioritizing which the lead link can help with.
Sometimes it is an ability issue and training is needed. Perhaps job specific training or just GTD training.
Doesn't sound like process break down it sounds like a tension to be brought forward and a conversation to have. Good luck!