Halochakli it is permitted if a chatzitza covers less than half the body (or heir) and it does not bother most of the woman like her (that have her profession)
But the minhag is lohathila for mikva no chatzitza at all,
( bidieved if like above (halochakly permited) then OK, (if went home already even more lenient (ask a Rabbi) so that people should not say bad things )
As to can see this brought in the beginning of this
Even the source you bring seems to permit it for hand washing also only bdieved (after the fact)
From the sources @kouty brought below it seems that rings are thing that are removed, so unless you are part of a type of women that does not remove them ever you halochakli need to remove them
But the source you brought (siman 127) hints that most women now do not knead dough so do not need to remove halochakli, but Baker's need to even if they do not since most Baker's do