High side MOSFET Driver component selection
The turn-on propagation delay is typically 680 ns and worst case 900ns. When driving at 1 MHz 50% duty-cycle,\$ t_{on}\$ = 500 ns.  So, you already turn off the gate driver, before it could drive LO or HO high.
So, this IR2184 is too slow to be driven on 1 MHz.
Next, without connecting the low-side mosfet, the bootstrap cap will not be charged, and therefore the high side driver will not work.