This may be old news to some of you, but I just found it.
https://carrietomko.blogspot.com/2006_07_02_archive.html

EMAIL FROM DR. BOND
Dear Friends,

Fr. Marshall Roberts, one of the founders of the suppressed Society of St. John, has found a new home as chaplain at St. Michael the Archangel in Jacksonville, Florida (http://www.saintmichaelarchangel.com).

In March 2002 I exposed Roberts as one of the ɧoɱosɛҳųαƖ predators of the Society of St. John. (See my original warning at http://www.saintjustinmartyr.org/news/MarshallRoberts[1].html.)

As a seminarian at the Institute of Christ the King in Gricigliano, Italy, Roberts was expelled in 1993 by the seminary's then vice-rector, Fr. Patrick Perez. Fr. Perez expelled Roberts for writing explicit love letters to a younger seminarian with whom Roberts was enamoured. The younger seminarian, who did not appreciate Roberts' advances, gave the love letters to Fr. Perez who then saw to it that Roberts was dismissed from the seminary within 24 hours.

Roberts later found a happier home with the Society of St. John where Carlos Urrutigoity and Dominic O'Connor gave Roberts the freedom to pursue a "particular friendship" with a boy who had caught his eye. The object of Roberts' affections this time was a student at St. Gregory's Academy who, upon graduation in 1999, joined the SSJ. Roberts and this boy occupied the same room on the SSJ's property in Shohola. When Roberts later visited the SSJ in France, Roberts was given special permission to spend time alone with this boy in his room after compline.

It should also be noted that Roberts was the first member of the SSJ to write to me in defense of Carlos Urrutigoity when I first exposed Urrutigoity as a ɧoɱosɛҳųαƖ predator who gave "spiritual direction" to boys while sharing a bed with them. Those who attend Mass at St. Michael the Archangel should ask Roberts whether he still believes that Urrutigoity is innocent, and whether Roberts himself is still pursuing boys and younger men.
Pax vobiscuм,
Dr. Jeffrey M. Bond


FR. MARSHALL ROBERTS
There is a letter online signed by him dated 1997, which explains his reasons for leaving the SSPX. Since the letter mentions Fr. Fullerton and Fr. Urrutigoity, I presume it is the same Fr. Marshall Roberts who is now associated with the Chapel of St. Michael the Archangel.

There is a St. Michael the Archangel Catholic Church in Jacksonville that once listed Father Fulham as the parish priest.

That is now an SSPX chapel.  I've visited it before, pretty sure it was Fr Roberts who celebrated Mass and heard my confession.  Nothing remarkable about the experience, nice little chapel.

https://www.stmichaelcatholic.org/

Fr. Marshall Roberts, aka Fr. Mary of the Pillar, now works behind the scenes with Pfeiffer of OLMC (KY) in Portales, NM.

Here is the address of that mass center, as of July 2020: 247 Stone Ranch Rd.Portales, NM

He might be.  I don't know.
I do know that as of March 2021 he was working with Pfeiffer, taking care of "fr. Pfeiffers flock" in Portales, NM.

I found these online, which i hadn't read about him before:

Twitter account
https://mobile.twitter.com/friaranthony62?ref_src=twsrc%5Egoogle%7Ctwcamp%5Eserp%7Ctwgr%5Eauthor

Father Marshall Roberts, an incardinated priest of the Diocese of Scranton, has reportedly assumed residence in Water Valley, Mississippi in the Diocese of Jackson. Since January 2005, Father Roberts has been unlawfully absent from priestly ministry in the Diocese of Scranton and does not have permission to exercise priestly ministry outside of the Diocese of Scranton. Furthermore, Father Marshall Roberts does not possess the faculty to validly hear confessions. Any inquiries about the priestly ministry of Father Marshall Roberts are to be directed to the Vicar General of the Diocese of Jackson: Reverend Lincoln Dall Chancery Building 237 E. Amite Street, Jackson, MS 39201 - 601-960-8476.
https://stjosephstarkville.flocknote.com/note/8869614


https://threadreaderapp.com/user/friaranthony62

YouTube
https://www.google.com/url?sa=t&source=web&rct=j&url=https://m.youtube.com/channel/UCAmcDH_dukOL_Pn-hXg9FPw&ved=2ahUKEwiV4J7ph4nzAhWnl2oFHbdJAiQQjjh6BAgJEAE&usg=AOvVaw1PQBmWf0jw4_iCU5EZQIO5&cshid=1631987075790

I although thought '10 Year Old Girl Productions' was an odd name.

I although thought '10 Year Old Girl Productions' was an odd name.

Well, she's 15 or so now...  

On the OP, this on SSJ is of interest.

https://www.newengelpublishing.com/exploiting-traditionalist-orders-the-society-of-st-john/#_edn60

Exploiting Traditionalist Orders The Society of St. John

LOTS of info about SSJ on the internet.  Read it on an empty stomach.
I wish there was a thread listing all the priests who started the SSJ or who spent a fair amount of time with the SSJ, and where they are now.  Very important to the safety of souls.