I did not know that this part of Plarium was outsourced, but, from an IT perspective, a lot of companies do this. The Service Level Agreement (SLA) should have been written by both parties and submitted to a board of both parties for review. For example:
Plarium-Show definitive proof of Help Desk ticketing system to include computer software (application used to track tickets) Include point of inception of ticket-from issue to cause to resolution.
Zendesk-with Plarium support engineers, creates "fail-safe" tickets and watche how ticket(s) flow in to Zendesk help desk, and tracked.
Basically after a "paper flow" and round table discussion(s), the two parties agree on a SLA (Service Level agreement). Both parties know "exactly" what hardware, software and infrastructure will be in place to support Plarium and, ultimately, for Zendesk to be paid.
Metrics: A huge part of SLA's are metrics! How many tickets did you respond to in 24 hrs, 1 day, 7 days..etc..
Plarium to Zendesk-can you graph which area we need to address-failed logins, loss of items, loss of drachs etc.? There should be categories implemented from Plarium to Zendesk: Show us "x"..show us "days logged in" etc..
Given the size of Plarium and Zendesk companies and the type of SLA that needs to be drawn up-it is probably a miscommunication between both parties (if in fact Zendesk has the contract) as to what they have to support.
Again, back to the round table and paper flow of incidents/tickets-I really can't hammer this home any further-sometimes we (I) have discussions with my clients (video teleconference etc..) for days on each and every process until both parties see "exactly" where "each" is causing a break in the chain of support
Hope they get it straightened out-it is a monumental effort on both sides to do it correctly so that the customer doesn't get left in the dust.