I removed the cracked lens today and refocused the laser mirrors sans the combiner lens. In my testing the power seems to be normal on both sides of the bed now. Unfortunately, removing this lens means we don’t have red point laser for aiming .
I have ordered a new lens which should be here within a week.
If we still power issues with the laser in the coming weeks, then it probably means the tube is dying and we will have to go through the process of replacing it.