3. Do I actually stand any chance of getting employed in the field considering I do not have a technical profile (political sciences, communication, history, development...)?

Yes, you do. The Junior Programme recruits from a variety of backgrounds, also so-called 'non-technical' profiles.
Some job openings are for 'soft' project aspects like raising awareness or mainstreaming gender, communication, or monitoring and evaluation.

Have a look at the examples of jobs of former Junior Experts on the website.