Cloud VPSes are currently pointed to a couple of recursor IPs, labs-recursor0 and labs-recursor1, that currently run in labservices cluster which is in itself in production.
This is non-ideal, as it creates yet another cloud->prod flow and escalation vectors in case of exploitation. These recursor should move within WMCS instances, e.g. in a couple of instances in the cloudinfra project, similar to what we did with smarthosts in T41785.
The only gotcha seems to be that the recursor runs some custom Lua code, that uses data generated by a Python script, that in turn seems to gather those from Nova's API. I'm not sure if that's accessible publicly or from within WMCS.
SRE can possibly help with the move, as long as we all agree on the plan and the Nova API -> VPS data flow gets figured out :)
Note that this is different that Cloud's authoritative DNSes (labs-ns0/labs-ns1); currently both recursors and authoritatives run as distinct services on the same servers, but there is not reason for that to continue to be the case (and they are distinct e.g. in production).
Also see: T119660, T200358.