Wow! I'm not sure you realise just how fortunate you are! I did near on 35 years Aero Engineer (Forces then Industry). I got a "Desmond" BTW. How many times did I "use" my degree? Erm, never! Not once! It was, effectively, irrelevant - unless, you go on into specific research/design/geek-mode.
I learned all I needed for all the jobs I did through equipment and other courses post-Degree. What counts is "practical engineering ability" which has more to do with you working on your car at home than any applications of Laplace Transforms or knowing the annealing temp for some exotic alloy! My Degree turned out to be a 3 year hurdle to be survived with "beer drinking skills" being the most, sorry, only useful skill derived from the 3 years!
So, you will be fortunate to have an initial career to help fund your flying and then act as a fall-back career should the flying go TU - as it will at times. I swapped between the 2 on a couple of occasions and then went back to Engineering for good when I unexpectedly lost my Medical quite early on.
So forget your "3rd" - and realise that you have a huge advantage which, like it was for me, meant I was never out of work for long! And I enjoyed both professions too! Yes, missed flying but also enjoyed my Engineering.
As to a degree being equivalent to ATPLs? Banana Joe is correct and, certainly for UK ATPLs, you often just had to learn what the Exam required as an answer. One got the feeling that, for a lot of it, you were learning how to pass a set of Exams - not what was really needed for flying. I'd suggest a "degree" teaches you how to think, ATPLs teach you how to "memorise". Maybe a tad simplistic, but that's how I see it. Others may well disagree (this is PPRuNe after all!).
So, bottom line, count your blessings for your future life, ignore the "3rd" as really not much of an issue and crack on! And good luck with both your careers!