Would see it as being a legit administered ordinance if was done in and by a duly authorized spiritual local assemble , and that was done by a legit NT Church.
We would respect the immersion by the PC, as would see them as being a legit NT church , but if they had infant baptism, would not see that as a legit one
The thorny issue in that case would be reformed churches, as they do uphold trinity, Gospel, just differ on view of water baptism mode and when to use it
Those who are into modern day prophets and Apostles and "revelations" coming to them from God would take to heart"touch not the Lords anointed" as mandate to allow their leaders to do some gross sinning
Which highlights difference between reformed Baptist and other reformed, as we see the New Covenant only instituted and valid with those who are actually in the NC, based upon them having received Jesus as savior and lord thru faith in him , and thus qualified for water Baptism
one of my pastors stated that whenever a pastor or teacher really makes an issue out of certain sinning in bible, that just might be the one area they are having hardest time dealing with themselves
You see this a lot in circles such as word of faith, as they have elevated their leadership to being modern day apostles and prophets, and pretty much what they do is excused under "touch not the Lords annoited"