set (real)VNC resolution on headless Pi 3B+

[Twist]

I can't replicate your 2000x1300 resolution... see code output below
Now planning to try some of the things mentioned here

Code:

pi@fluxpi:~ $ tvservice -s
state 0x40001 [NTSC 4:3], 720x480 @ 60.00Hz, interlaced
pi@fluxpi:~ $ fbset

mode "1920x1280"
    geometry 1920 1280 1920 1280 32
    timings 0 0 0 0 0 0 0
    accel true
    rgba 8/16,8/8,8/0,0/0
endmode

pi@fluxpi:~ $ vcgencmd get_config int
aphy_params_current=819
arm_freq=1400
audio_pwm_mode=514
config_hdmi_boost=5
core_freq=400
desired_osc_freq=0x33e140
desired_osc_freq_boost=0x3c45b0
disable_commandline_tags=2
disable_l2cache=1
disable_splash=1
display_hdmi_rotate=-1
display_lcd_rotate=-1
dphy_params_current=547
force_eeprom_read=1
force_pwm_open=1
framebuffer_height=1300
framebuffer_ignore_alpha=1
framebuffer_swap=1
framebuffer_width=2000
gpu_freq=300
hdmi_blanking=2
hdmi_force_cec_address=65535
init_uart_clock=0x2dc6c00
lcd_framerate=60
mask_gpu_interrupt0=1024
mask_gpu_interrupt1=0x10000
over_voltage_avs=62500
over_voltage_avs_boost=0x2932e
overscan_bottom=32
overscan_left=32
overscan_right=32
overscan_top=32
pause_burst_frames=1
program_serial_random=1
sdram_freq=450
second_boot=1