Jawa 500 884 oil mixed with fuel + oil level banjo broken

[G]

Bit of a niche question, but I can see at least Ariel has had involvement with them...
I've got a Jawa 500 884 in lay down configuration.

First off, due to a gummed carb, methanol got mixed with the oil. It was run a bit like this, but never under load.

I'm flushing it several times cold with cheap oil, then going to do it a couple of times with R40, then another flush or two with R40 with it running.
Should that be ok? I've ordered a USB endoscope and will have a look down the bore.

In the process of looking at the issues, I also managed to snap the (already weakened, I reckon ... my excuse ) upper oil level tube banjo. Got one on the way, but probably won't be with me until Friday and ideally want it running before then. Can I run it without it? Presume it shouldn't cause any problems and they are basically merely two tapped holes in the crank case, so can be blanked?