It wouldn't be great but I'm not sure if it'd make a huge difference to the outcome and would probably cause the house of cards to collapse in Belarus. Didn't they need Russian troops to restore order after the last election 'win'? I suspect if their soldiers enter then Lukashenko would be toppled soon after - either by his own generals when thousands of their men are killed doing Putins bidding, an enraged civilian uprising who don't have to fear the army (and no doubt heavily armed by Ukraine) or both.
If they didn't go in at the start when they were sure of the outcome (sounded like the army outright refused at the time?!) then I really doubt they'll go now against a much more mobilised and armed Ukraine.
But agreed, it's not a headache Ukraine needs right now and would cause more catastrophic loss of life and damage to infrastructure so they won't be officially doing anything unless Belarus really start taking the **** even more than they have. Don't get me wrong - with what they've done already Ukraine would have every right to officially declare war on them imo!
The only good thing here is Lukashenko is damned if he does or doesn't now. Go in and probably lose power soon after. Don't and assuming Ukraine essentially wins then Russia will be in no condition to prop him up anymore and any uprising will be fully supported by Ukraine.
I suppose he could try folding Belarus in under Putin's ussr mrk2 which I reckon he was going for before Ukraine stuck a thorn in his paw. But that would be civil war too.
