The longest column looks like "Acceded ti-Ajaw [name] Bacab."

Does the scene look as if it could be representing an actual accession event?
Or some event after that?

I though I might contribute with some thoughts on this one, in the hope it will stimulate others to also do so. So here goes:

In terms of style, the vase is very similar to #s: 2784, 2803,3008, 5506 and 6316.

Vase 2784 has reference to Namaan lord, text is by a son of Sak Muwaan, lord of the Ik' site.

Vase 2803 names a /"spangle-head" ti' k'awiil/ as vase owner and

names Sak Muwaan of the Ik' site as one of the ballplayers.

Vase 5506 likely names a Sak Muwaan (from the Ik' site?) as the vase owner.

This may point to a regional style associated with the area between Motul de San Jose and the Namaan polity (La Florida?) including Hix Wits (El Pajaral). The vases are usually dark yellow background with the characters often depicted with darkened bodies.

The main (non PSS) text is rather interesting. It speaks of an acession. Indeed, the same motif appears to be the central message of vases 2784, 6316, the texts being very similar in structure.

In 8469 however, the main text starts in a very enigmatic way:
b'ahlun "chin strap"
?-?-NAL
K'UH-CHAN-NAL

"chin strap" is a glyph recently identified by David Stuart as being associated with 9 year calendar periods at Tonina(see article at Mesoweb site). Interestingly it seems preceded by a 9 here.

u-B'AH
(ti)-HOY
AJAW yu-?
B'AHLAM
b'a-ka-b'a

"the image of being enthroned ? jaguar, the first earth".The name of this character is difficult to read, apart from the fairly evident /yu-/ prefix to the head variant.