Belgian nationality - work, student? part time?

Hello all, I've been in Belgium the last 2 years, and would like to stay at least long enough to become a Belgian citizen. However, my workplace is incredibly toxic and I'm concerned for my long term-mental health. I've been told as a non-resident if I move to a second job within Belgium, I'll be taxed as a resident (can someone confirm this?). I'm trying to see if I can reduce the time spent at work by either going part time combined with a part time masters, OR a PhD, OR just working part time at my job. Does anyone know how this affects the 5 social integration criteria or the economic participation criteria? thank you very much!

Also, are there services for workplace audits? There is a history of sexism and misconduct at my company and reports to HR have been of no help. It'd be nice to make a positive change.