Turning out this is due to the greedy matching of host_regex: 'c.*' pattern, it is fixed after change it to host_regex: 'c.*?'
I also create a PR to solve this from OOD’s side as it would be hard for users to figure it out from their side: fix node proxy location match pattern by link89 · Pull Request #2784 · OSC/ondemand (github.com)