not all degrees are equal
Isn't that the truth!
A good flight test team (minimum one tp one FTE - but of course could be much larger) must be able to cope with everything that the programme involves between them.
Depending on the aircraft type this may require the maths of advanced flight control systems and if there is flight control software involved then software maths is another must.
Maths at college was not my strongest point (that is what people say about their worst subject is it not?) but the tp in even the minimum team does bring other skills to the team effort so I would never suggest that excellent maths was a pre requisite of a tp.
However he/she must NOT have a chip on their shoulder that says maths is not important (like some I have known) and their ability to sit down with those who do have maths skills and no matter how long it takes help them understand what went on in the aeroplane is VITAL
Personally I think there is a case these days for a Flight Test degree laid out in modules. This degree syllabus would fully encompass all the roles of tp and FTE but there would be a choice in which modules you chose. For example the advanced flight test and aircraft system maths module or the aircraft handling/airmanship piloting side - to name but two possible valid modules