@dannyappa 

Danny,  Yes you can use two extenders at one time, but there are a few things to consider. 

Placement:  Extenders should be place in opposite directions form each other.  So If the RE355 is on the north side of the house the RE650 should be on the south side.

Setup:  Extenders should not be daisy chained, doing so will make the connection almost unuseable.  To Advoid this, configure the extenders 1 at a time.  After the 1st one is configured unplug it and setup the 2nd one.  once that is configured you can place the extenders in the desiered locations. 

with the RE650 only having the 2.4GHz light on it could mean 1 of two things.  Either Highspeed mode is being used or the 5GHz was not configured during its setup.  High speed mode is when one band is used to talk to the router and the other to the endpoint devices.  

If you clone the SSID  and if you Verizon router uses a single SSID for both bands then you will only see one network name.  

My recomendation would be to reset both extenders and configure them one by one.