I haven't seen anything to suggest that PLA is after the GGRM.

I do think the PLA did a very statesmanlike thing when they agreed to store some of GGRM's equipment. With all the petty rivalries that go on in the museum world, this was a very
gracious thing for them to do, and they had to spend a lot fo theri time and money to help make room for GGRM's stuff.

They could just as easily have said "no" and if they had, GGRM would have been very hard pressed to find any place else. Even though they've (GGRM) known for years that they would eventually have to get out of Hunter's Point, the new board did little or nothing to find even temporary quarters, much less anyplace permanent. I guess they were waiting for elves to bail them out.

The Portola people and PLA have gone above and beyond to bail GGRM out of this crisis, at least for the short run. GGRM may yet implode or it may not, but if it does, at least most of it's equipment collection is in a relatively safe place.

As for handing out flyers, I don't know whether or not anyone had permission. I do know that it's common for groups running trips to allow other groups to hand out flyers on the trains as they run. IME, it's a little unusual, but probably not unheard of, for this to happen in a museum setting.