"slip between the crutch and the anchor arbor has come back to haunt me. The pendulum can be set in motion again but the verge doesn't engage properly with the escarpment wheel".
Ok, not saying I know this particular movement as it is older English.
Two connection points on a probably round steel arbor. The anchor (aka verge (pondism term)) and the crutch.
Both probably use brass collet. A collet simplifies manufacturing process in some circumstances. Easier to replace. Otherwise it's just a hole. A bushing is a hole that a pivot turns in.
The crutch collet is usually a solid fit. Meaning you can count on no slip. But again yours could be different.
The anchor collet otoh is often designed to slip. This is a feature intended to automate putting the clock into beat. The idea being that the force of the pendulum swinging, especially if pushed to excess at begining, forces the slight/loose friction fit of the anchor to give and eventually balance out, putting clock into beat.
But, this doesn't always work reliably. Over time they tend to get too loose and stick out of beat.
If this is your situation, a simple solution is to scar up the arbor surface where the anchor would normally reside with a pair of dykes/wire cutters. Then slide anchor back. Measure anchor distance from an end before moving out of way, to avoid losing original location.
The anchor repositioning is safer done with arbor upright clamped in bench vice and needle nose held horizontally on top of both side of anchor, then gently tap pliers at hinge to slide anchor down arbor out of way. The vice holds arbor nothing touches pivots. Another way to do it is to clamp anchor in bench vice and tap on end of arbor with one of your hollow punches. But this way risk pivot damage, as you can easily break a pivot. What you will find on your staking set is that they are designed more for watch work with watch sized gears and arbors. Sometimes clock parts fall within size ranges but not often. Using the jaws of bench vice slightly gapped serves as another way, where anchor rest on top of jaws and arbor slides down gap.
Of course when you mar the arbor surface you want to go lightly on it. Just enough to see plier marks. What this will do is increase the friction fit. So not only will it be tighter but still compliant so to be adjusted.
It makes no sense that both connection to be solid, unadjusting. Because this is how a clock is put into beat. The only other way I know of is when the crutch is just a wire that can be bent so to change beat angle. Your crutch is not a wire or intended to be bent.
So whatever uses the pins (I have some confusion in your description) the anchor or the crutch, that probably is rigid. The other friction fit designed to slip a little.
Auto beat are annoying. Probably all Grandfather clocks are auto beat, I don't know. Kinda like all Cadillac have powered seats. But sometimes they fail.
I have a few Grandfather clocks like this. Some I haven't bothered to fix. A trick is to start pendulum with an aggressive push and slightly bumps other side of case. Then listen for the tick-tock to be even spaced (in beat). If no go switch sides. When and if it goes good it seems to stay put till next time. So I wind up before it quits. If it gets out of whack while running then you have to do the arbor scratch.
