your schematic looks more like a Kuroda amplifier than an Alexander amplifier and it seems that there’s nothing wrong. I’ve simulated with LTspice , with reliable spice models of MJL1302A, MJL3281A, MJE340, MJE350, BD139, BD140, TIP41C and TIP42C, and it works fine. Try to test the same models into Multisim.