Those are completely different cases, for one
There are. For one the north stream's potential ecological disaster would affect all countries around the Baltic sea. Whereas if Poland would have chopped all her trees to pieces, it would affect only Poland. Also it would be reversible in a few decades or in a 100 years you could have pretty much reforest the place.
In the case of the North stream the result of a disaster would be much more severe and most likely not completely reversible - at least the moment.
Just to drive the point home a case that illustrated well double standards:
Germany are pushing/supporting the EU interfering into internal Polish affairs that has no legal grounds nor legitimacy to do so. Those measures are well outside EU agreements.
Not long ago in Bavaria in the similar cirncumsctens Germans chopped up their infected trees - not a murmur from The EU and the German press supports it whole and those few ecologist/activists who dared to protest - terrorists.
So, you fairy story about great EU and Poland who is a bad apple is just a story to justify double standard, interference, incursions German and the EU deem justified, Well Polish people disagree. Take that.
The flaw in your logic is that Germany has not the influence you seem to believe.
Come on. Not as great as believe? what kind of measurement standard is that? I'm talking about facts.
Germany and France are influential. They can get away with bending EU laws, breaking it, or with doing whatever they deem right. Others should just walk the line. If they dare to stray a little or follow Germany example woe to them!
That is not how you build a Union. You build it giving an equal footing to all the countries involved. In such a politically delicate construction whether or not a country is big, small, a power house or economically insignificant it should not have affect their voice or their rights. IF the EU is to work and to be something other than a hegemony where a one orders and others obey Germany needs to see to it.
More powerful, richer and bigger countries will be more persuasive anyway as a matter of course. You need do away with that blatant double standards practice and that dimwitted and dumb Prussian idea of an order.
The way it goes seems to me it goes in the direction of the hegemony not the union. Hence I don't think it would be practicable for Poland to participate in such an endeavor.