TD, was the grub a short fat, up to 1cm I guess, white 'C' shaped thingy with a red/brown head that doesn't appear to have legs?? If so it sounds to me like a Vine Weevil grub, oh-oh. I see you are from the US so I dont know if you get these. The grubs eat the roots and can wipe out plants potted in peaty soils which they prefer. The adults eat holes in the leaves. Specific Vine Weevil douches can get rid of them as can hand picking them but this is difficult as every nook and cranny of the soil & especially the rootball, has to be inspected.
Not sure what VW eggs look like, but know that slug/snail eggs are also clear/milky white in colour. Also, read somewhere that somebody thought their compost was infested with eggs only to find out they were 'Osmocote' fertiliser granules! Crush one, if it bursts and is fluid filled you have eggs...get rid of them!!! If its hard/crumbly it's a fertiliser...leave alone!!
Post a pic if you can, or google Vine Weevil grub and compare.
Gill.

Go to gallery and look at my pic post,i took a picture of them..TD