2001 toyota avalon door lock/unlock

I'm installing a Viper 5704 in a 2001 Avalon which, according to a bit of research, has some sort of lock detection circuit.  In many of the install guides, it shows going into the door and tapping into 3 wires using a relay and a pair of diodes to allow the keyless entry to work the locks, as seen here:

https://www.the12volt.com/installbay/uploads/37Z_1070.pdf

http://www.bulldogsecurity.com/diagrams/extrainfo/diagrams/14301_AVALon_TOYOTA%20and%20LEXUS%20door%20lock%20interface.pdf

http://documents.audiovox.com/700664.pdf

I didn't have any diodes on me so instead of this approach, I went directly to the door lock switch in the door.  The lock/unlock buttons simply connect the respective circuits to ground.  So I wired the output of the Viper to those buttons and in effect the Viper is now pressing the lock/unlock buttons.

So far it seems to work.  I've seen many posts about having to use the relay and diodes to properly interface the door ECU.  Is the way I did it wrong or is there some other benefit of using the relay and diodes?  Thanks for your help.