First, like you said, you get privileges removed as a warning... if it keeps happening, then you get private reproof... then public reproof... then you're disfellowshipped.
You were an elder, you should know this.
Agree it is partly true, only because there is elder discretion here.
You could get disfellowshipped for it if the elders pursue the only charge that relates to this which would be "Brazen Conduct" and only if they were either critical of the disfellowshipping or were having spiritual association in the form of worship.
In my experience I counselled many dubs on associating with DF ones, some repeatedly over many years but we never disfellowshipped them for it.
The elders hand book states on page 116 paragraph 6:
If members of the congregation are known to have undue association with disfellowshipped or disassociated relatives who are not in the household elders should counsel and reason with those members of the congregation from the Scriptures.
Review with them information from the "God's Love book, pages 207-208; The Watchtower of April 151 1988, pages 26-30; or the article "Display Christian Loyalty When a Relative Is Disfellowshipped in the August 2002 Our Kingdom Ministry.
If it is clear that a Christian is violating the spirit of the disfellowshipping decree in this regard and does not respond to counsel, it may be that he would not qualify for congregation privileges, which require one to be exemplary.
He would not be dealt with judically unless there is persistent spiritual association or he openly criticizes the disfellowshipping decision.