I've never taken mine apart, but from looking at
this PRS-350 tear-apart video, it looks relatively easy to get a better look at, and better access to, the reset hole: remove the one bottom screw and use a spudger or plastic guitar pick or strong fingernail to partially remove the plastic edge cover that covers the reset hole.
The video also shows simple removal of the back cover, if that is needed for further access.
Here's the
manual, which shows more screws holding the chassis assembly, in case you have to dig deeper.