How bad of a mistake is this, and can it be fixed?

[Scott Cenicola]

Looks awesome! I promise I'll never tell.

[Sam Murdoch]

And so now you have a bunch of clever solutions that outweigh the need for a cleaver solution

Great project and nicely done, even considering your "mistake".

[Bill McNiel]

Woodworking is not about not making mistakes, its about making your mistakes look intentional. It'll be fine.

[Al Launier]

I believe you are good to go as is. However if this is going to remain on your mind, then I think Lee's concept is the simplest & would add a good deal of strength. What I would change though is use a wood screw that is #10 with the head of the screw buried in the c'bore, as Lee suggested, but take it one step further and that is to make a couple of plugs of the same material, glue into the c'bored holes with the grain orientaion aligned with the adjacent grain, then sand flush.