The 'TrickToFixNasParams' network must be the last network. Otherwise, this hack will not work.
You can do it, editing /etc/config/wireless like this:
config wifi-device 'wl0'
option type 'broadcom'
option channel '1'
option txantenna '3'
option rxantenna '3'
option country 'BR'
option frameburst '1'
option htmode 'HT40'
option txpower '14'
option hwmode '11g'
config wifi-iface 'default_wl0'
option device 'wl0'
option network 'lan'
option mode 'ap'
option wmm '1'
option ssid 'My SSID'
option encryption 'psk2+ccmp'
option key 'mypassword'
config wifi-iface 'wifinet1'
option device 'wl0'
option network 'lan'
option mode 'ap'
option wmm '1'
option ssid 'My another SSID'
option encryption 'psk2+ccmp'
option key 'mypassword'
config wifi-iface 'wifinet2'
option device 'wl0'
option mode 'ap'
option ssid 'TrickToFixNasParams'
option encryption 'none'
option disabled '1'
Using Luci, I think you need remove 'TrickToFixNasParams', and recreate it after create your additional wireless network.
But Luci interface doesn't work to show connections info with broadcom-wl drivers.
The last version that Luci wireless interface worked correctly was Lede-17.01.7.
Using ssh interface, you can get wireless info using iwinfo (replace <iface> by wl0, wl0.1 etc):
iwinfo <iface> assoclist
As the package is proprietary code, it has not been maintained for a long time.
Unfortunately the open source driver for these broadcom chips was basically made using reverse engineering. So they perform much less than proprietary drivers.