Asking a question to get a useful answer for others is allowed, and even encouraged, on SE sites. You can even offer your own answer before posting the question, if you feel the question is common enough, and the answer important enough to be included on the SE.
I would not encourage you to lie about your qualifications - if you're asking this question hypothetically, you should say so specifically in the question, and provide a realistic scenario where one might actually need the answer you're trying to find.
Additionally, if you do opt to provide an answer, keep in mind that all the rules about basing answers on actual knowledge and experience still apply.
For your specific case, your actual question is a good one, so I would take care not to edit out the details of the question if you choose to alter it to be more 'honest'.
You could (and should) also ask on the Travel.SE Meta - they may have different rules regarding qualifications for questions that general SE sites don't.
Personally, your question looks useful and has resulted in an informative answer, so I don't see any huge problem with it as-is, but in the future, you don't need to be afraid of asking questions you either already know the answer to, or simply want to ask to add to a site's wealth of knowledge.