While this job opportunity might be merited by Oscar's good work for the City, there are a few rules he must follow in order to apply for the job.
In order to avoid the appearance of impropriety, Oscar is prohibited from pursuing a job offer with any company with which he is actively working on his City job.
Before he may go on the interview, he must wait for his work with Veronica's company to be completed. Or, he can have himself taken off the project. Then he can go on the interview.