Assuming you have \\.\DISPLAY1 as your LCD (enabled as primary desktop) and \\.\DISPLAY2 as your CRT (enabled as secondary desktop).
From command-line: mame64 sf2 -screen \\.\DISPLAY2
This should launch GM on your CRT. If this doesn't work, then please post a log so I can see what's going on.
I tried it and it made my crt flicker like it was about to load then got the following in the command line window...
L:\LaunchBox\Emulators\Mame Groovy>mame64 sf2 -screen \\.\DISPLAY2
SwitchRes: [sf2] (1) horizontal (384x224@59.637405)->(2560x224@59.637405)
-----------------------------------------------------
Exception at EIP=00007ff9989ea146 (register_frame_ctor+0x8fb081e6): ACCESS VIOLATION
While attempting to read memory at 0000000000000048
-----------------------------------------------------
RAX=0000000000000000 RBX=00000000116b0b88 RCX=0000000000000001 RDX=0000000000000000
RSI=0000000000000001 RDI=00000000116b0b88 RBP=000000000ef0ea30 RSP=000000000ef0e930
R8=0000000000000008 R9=0000000000000000 R10=00007ff9cac615c0 R11=000000000ef0e984
R12=0000000000000000 R13=000000000ef0ef80 R14=0000000014ee3f78 R15=0000000000000000
-----------------------------------------------------
Stack crawl:
000000000ef0ea90: 00007ff9989ea146 (OpenAdapter+0x553b6)
000000000ef0ed50: 00007ff9989786a5 (DllMain+0x6a65)
000000000ef0ef30: 00007ff99897997d (DllMain+0x7d3d)
000000000ef0efd0: 00007ff998979ca2 (DllMain+0x8062)
000000000ef0f040: 00007ff9acd8998e (register_frame_ctor+0xa3ea7a2e)
000000000ef0f0d0: 00007ff9acdba5dd (Direct3DCreate9+0x9dcd)
000000000ef0f150: 00007ff9acd8a7f8 (register_frame_ctor+0xa3ea8898)
000000000ef0f2c0: 00007ff9acd8b49a (register_frame_ctor+0xa3ea953a)
000000000ef0f310: 00007ff9acdbdc48 (Direct3DCreate9+0xd438)
000000000ef0f360: 00007ff9acdc682e (Direct3DCreate9+0x1601e)
000000000ef0f3e0: 000000000265dce4 (renderer_d3d9::device_create_resources()+0x0434)
000000000ef0f470: 000000000265e1d3 (renderer_d3d9::device_create(HWND__*)+0x0363)
000000000ef0f4e0: 000000000265ea4c (renderer_d3d9::create()+0x00dc)
000000000ef0f5f0: 000000000262146a (win_window_info::complete_create()+0x041a)
000000000ef0f900: 000000000262207c (win_window_info::create(running_machine&, int, std::shared_ptr<osd_monitor_info>, osd_window_config const*)+0x09bc)
000000000ef0f970: 000000000261d8cb (windows_osd_interface::video_init()+0x008b)
000000000ef0fa90: 000000000260dc85 (osd_common_t::init_subsystems()+0x19c5)
000000000ef0fd90: 0000000002605b9c (windows_osd_interface::init(running_machine&)+0x02cc)
000000000ef0fe90: 0000000003f98134 (running_machine::start()+0x0364)
000000000ef0ff30: 0000000003f9a030 (running_machine::run(bool)+0x0060)
000000000ef1f210: 00000000026c384a (mame_machine_manager::execute()+0x020a)
000000000ef1f4c0: 0000000002731984 (cli_frontend::start_execution(mame_machine_manager*, std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const&)+0x03f4)
000000000ef1f630: 0000000002731e45 (cli_frontend::execute(std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&)+0x0045)
000000000ef1f690: 00000000026c17ea (emulator_info::start_frontend(emu_options&, osd_interface&, std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&)+0x002a)
000000000ef1fe50: 0000000008cf965d (main+0x016d)
000000000ef1ff20: 00000000004013f7 (__tmainCRTStartup+0x0247)
000000000ef1ff50: 000000000040152b (mainCRTStartup+0x001b)
000000000ef1ff80: 00007ff9c86b8364 (BaseThreadInitThunk+0x0014)
000000000ef1ffd0: 00007ff9cabb70d1 (RtlUserThreadStart+0x0021)
EDIT>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
I then tried with display 1 incase windows is reporting dispay number wrong and got the following.....
L:\LaunchBox\Emulators\Mame Groovy>mame64 sf2 -screen \\.\DISPLAY1
SwitchRes: [sf2] (1) horizontal (384x224@59.637405)->(640x480@59.637405)
sf2e_30g.11e NOT FOUND (tried in sf2 sf2)
sf2e_37g.11f NOT FOUND (tried in sf2 sf2)
sf2e_31g.12e NOT FOUND (tried in sf2 sf2)
sf2e_38g.12f NOT FOUND (tried in sf2 sf2)
sf2e_28g.9e NOT FOUND (tried in sf2 sf2)
sf2e_35g.9f NOT FOUND (tried in sf2 sf2)
sf2_29b.10e NOT FOUND (tried in sf2 sf2)
sf2_36b.10f NOT FOUND (tried in sf2 sf2)
sf2-5m.4a NOT FOUND (tried in sf2 sf2)
sf2-7m.6a NOT FOUND (tried in sf2 sf2)
sf2-1m.3a NOT FOUND (tried in sf2 sf2)
sf2-3m.5a NOT FOUND (tried in sf2 sf2)
sf2-6m.4c NOT FOUND (tried in sf2 sf2)
sf2-8m.6c NOT FOUND (tried in sf2 sf2)
sf2-2m.3c NOT FOUND (tried in sf2 sf2)
sf2-4m.5c NOT FOUND (tried in sf2 sf2)
sf2-13m.4d NOT FOUND (tried in sf2 sf2)
sf2-15m.6d NOT FOUND (tried in sf2 sf2)
sf2-9m.3d NOT FOUND (tried in sf2 sf2)
sf2-11m.5d NOT FOUND (tried in sf2 sf2)
sf2_9.12a NOT FOUND (tried in sf2 sf2)
sf2_18.11c NOT FOUND (tried in sf2 sf2)
sf2_19.12c NOT FOUND (tried in sf2 sf2)
buf1 NOT FOUND (tried in sf2 sf2)
ioa1 NOT FOUND (tried in sf2 sf2)
prg1 NOT FOUND (tried in sf2 sf2)
rom1 NOT FOUND (tried in sf2 sf2)
sou1 NOT FOUND (tried in sf2 sf2)
stf29.1a NOT FOUND (tried in sf2 sf2)
iob1.11d NOT FOUND (tried in sf2 sf2)
c632.ic1 NOT FOUND (tried in sf2 sf2)
Fatal error: Required files are missing, the machine cannot be run.
But when running the mame64 exe it outputs to the lcd in 480