To be clear, there are no new "RGL ping guidelines". There are no new ping guidelines that create a limit of "110 ping" to NA servers.
The rule in question refers to this:
https://media.discordapp.net/attachments/776052661454635008/887057802877603890/unknown.png
This is an update to the Region rule by reverting it to a previous iteration of the rule that existed in RGL prior to the start of 2021 (the rule itself had existed since the beginning of the league). It is a region cap on the number of non-region players in the North American leagues for RGL (2 for 6s, 3 for HL, etc.). When RGL hosted European and Australian regions in its league, there were region caps on North American players participating in these tournaments as well.
Other leagues such as RSL.tf and UGC also have similar region cap rules:
https://media.discordapp.net/attachments/776052661454635008/887094856961388574/unknown.png
UGC:
https://media.discordapp.net/attachments/776052661454635008/887095033927458846/unknown.png
(* UGC making an exception to Colombian / Peruvian players)
The full article, which explains more in detail about why the the rule was reverted can be found here: https://rgl.gg/?a=1566. In a 2020 article, this was also polled where the rule was clarified/explained: