If the question can be paraphrased as "when colocating multiple job (templates) on a single VM, will they start in parallel or instead in some sort of order?" then the jobs will generally come online in parallel unless one job has a monit-level dependency on another, in which case monit will start them in order of the dependencies.
Given you are colocating jobs which are usually on multiple VMs and hence the ordering would be handled by bosh jobs (bosh-level dependencies), these job templates will not have monit-level dependencies configured and so you will likely see most jobs starting together. This may or may not work; we haven't tried starting all jobs in parallel.
The serial: true configuration in the bosh manifest applies at the bosh-level to multiple VMs, but as you only have a single VM it has no effect.
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