I work in a software engineering company with over 1000 engineers in silicon valley. We generally have really strong & healthy engineering teams, and have very high ratings on glassdoor. But occasionally there will be a bad apple that will skirt requirements/due diligence at the expense of other teams. Normally on Workplace SE, the suggestion for dealing with these problems is to document and escalate it, but for one particular team, this only worked in the beginning. It would go on to adapt, making its actions hard to document/track and even getting higher stakeholders to forget things that they decided in the first place.
Imagine a Team Bob: Team Bob has a project on its roadmap to deliver a customer-facing tool for estimating rainfall. Team Bob delivered a similar project in the past to very poor reception due to lacking a UI, and the new project also does not have a UI. It gets rejected in the executive review & UI mandated prior to release. The executive team suggests integrating this project into a tool that Team Alice owns. A quarter later, Team Bob has finished the non-UI half of the project and asks Team Alice to take over the UI portion, without advance notice. Team Alice gets input from the executive team who decide to cut one of Team Alice's original roadmap deliverables in favor of the UI for Team Bob's feature.
Team Alice communicates to the executive team up front how much the project will take (a whole quarter), but by this point Team Bob's promised delivery date for the feature is up. To excuse the delays, every week or so Team Bob passive aggressively mentions to the executive team that Team Bob's work (the non-UI half) is already done and Team Alice is blocking the release of the feature, even though Team Alice was only just involved. Team Alice tried to take the high road and ignored it, avoiding a grade school shouting match. Through repetition though, Team Bob convinced the executive team that it was really Team Alice delaying the project, even though the executive team agreed on the added cost upfront.
There was a lot more unprofessional behavior, but I will omit specifics for brevity. Team Alice attempted to surface these issues throughout the course of the project, but Team Bob reported directly to the executive team, so the executive team was the only medium that could intervene. It went well at first: when Team Bob would email Team Alice asking for permission to ship the feature without UI, Team Alice clarified the permission wasn't theirs to give and cc'd the executive member that owned the project. After this repeated & Team Bob got chewed out by the executive team a few times, Team Bob resorted to underhanded means. Team Bob would only show their true colors in face-to-face meetings. If Team Alice surfaced issues that happened there, then Team Bob would tell the executive staff Team Alice must have misunderstood them. Due to the executive team's busy schedules, it was not possible to invite them to the meetings. Eventually the executive team questioned if Team Alice had a grudge against Team Bob that caused them to escalate all of these (according to Team Bob) minor misunderstandings to the executive team.
How can Team Alice deal with Team Bob in such a way that 1) it is not exhausting, 2) Team Alice does not get blamed for anything resulting from Team Bob's subterfuge, and 3) Team Alice's product does not suffer at the hands of Team Bob?