I really hope you get the DSI to LVDS converter running and write a tutorial on how you did it. Which operation system are you bringing this up on? I am going to assume Debian in the response below.
A little background and things that might cause you grief as you get this project running. First the 410 processor on the board only has one DSI output, this output is multiplexed between the ADV7535 and the High Speed connector. In general it tries to use the ADV7535, unless all of the conditions are correct for it to fall back to the High Speed connector. 1) the HDMI SEL dip switch on the bottom of the board must be 'open'. 2) the HDMI HPD signal must be absent do not plug in a cable and monitor). 3) the DSI_SW_SEL (GPIO_32) signal must be 'high'.
The device tree entry for your DSI driver will need take control of 'gpio32' and set it high.
Your DSI display driver will need to set the correct timing and display size to match your LVDS display. I believe you have a DSI to LVDS bridge chip (possibly a TC358764XBG ??) it will need a I2C driver for this chip, perhaps you can use the ADV7511 driver as a starter template.
Setting the DSI timing, you can find some hints here: https://developer.qualcomm.com/download/db410c/dsi-display-porting-guide-linux-android.zip
The chip on the board is the ADV7535, but in the code it is called ADV7533, for the purposes or SW they are the same thing.
Full disclosure: I am an employee of Qualcomm Canada, any opinions I may have expressed in this or any other posting may not reflect the opinions of my employer.