Just my 2p on Jet2.com...

I make about 6-7 return trips on the MAN-IBZ route every year, and this year I've totally stopped flying Jet2 - they just seem to have way too many incidents for my liking. Last year there was the engine that caught fire taking off from IBZ, another one with hydraulic problems taking off from MAN, and I've also experienced a few minor tech issues with them myself, one time involving 4 hours sat on a boiling hot plane on the runway at MAN with no water provided which sounds rather similar to what happened to you.

Nothing against LCCs per se, but at least on Ryanair / Easyjet, the planes are new. Jet 2's fleet has an average age of 22 years. Of course age isn't an issue when the maintenance is solid (I mean, I fly AA domestic in the US all the time), but the combination of old planes and a very cheap airline doesn't seem to be a good one. And purely going by my own non-statistical anecdotal evidence, for each of the the last 3 years I've had more tech issues in my handful of Jet2 flights than I did in the other 150-200 flights I took on other airlines put together

Anyway something about this particular airline makes me very ill at ease, hence numerous trains down to LGW this year for the regular IBZ trips on BA (and I can fly Club too).

Good luck with the compensation.