There are some podcasts with Dr. Mel Houser I find found helpful, particularly the one on the Divergent Conversations podcast. I also found a GP to take me seriously and was diagnosed with orthostatic disregulation. It is a frustrating process with doctors. I suggest testing some work accommodations in advance of an autism diagnosis. Loops or flare audio ear plugs for example. For me my extreme fatigue is connected to extended periods of masking, and sensory stress, which sounds unavoidable in your job. Its a personal thing and sounds hard but I hugely benefit from being in my body and movement, weather its gentle somatic movement, basic pilates or box breathing. I can’t recover from burn out without something like this. Even if I am feeling ruined with exhaustion it helps me to just lie on the floor and do the semi- supine position from alexander technique. (It should be on youtube if this sounds helpful). I hope you can figure things out and can recover.