You should be ok with a good backing plate. The glass is thin right there as it is not designed as a stress point. Also realize that installing the new rod holder with backing plates is a fairly difficult job. For access you will need to:
Remove the lid from the livewell
Cut the sealant along the top edge
Reach in from the port or stbd battery compartment and disconnect the water supply and the overflow. It may be easier to remove the hose from the pump and leave the hose connected to the livewell, the plastic barbed fittings on the livewell are prone to breaking if you torque on them and the hose is a pia to remove.
Check for leaks in the whole sytem before resealing the livewell. People sink their boats every year due to a problem somewhere in the livewell and associated plumbing.
Find a small guy with long arms and you'll be set!