I'd think the chances of a conventional military attack on Poland, by Wagner acting on behalf of the Russian state are about zero - but sub-threshold, little green men, terrorist type stuff? Yeah, I can see that.
I rather doubt Lukashenko is remotely interested though - he's a man with his eyes on the future, and one thing he's good at is talking billy big bollocks with Big Vlad in order to get political/security/economic support for his dodgy government, while doing absolutely nothing that would seriously antagonise the NATO eastern states.
He's no fool. He can see that the tea leaves are somewhat muddied - he's pretty unlikely to throw the very delicate political balancing act that keeps him in power onto the fire for someone who may not be there is 6 months.