Yes. It seems Fr. Aldalur was some months with the capuccins. I remember to have seen a photo of him as a friar.. beard included... even with a religious name. Maybe he saw that it wasn't his place and then returned to the SSPX. I got the impression that he has never been in contact with the Resistance.
At the time of the 2017 French announcement, Morgon would have been considered by many (not all) Resistance:
They had just discretely published a book against an accord with modernist Rome, which they presented to Bishop Fellay; they declared that if their Ordinations were to be denied again that they would seek out the services of Bishop Faure or Williamson; they signed onto the the Letter of Seven Deans
condemning the new marriage guidelines; and with the (apparently temporary) addition of Fr. Aldalur to Fr. de Cacqueray and Fr. Paul Morgan, were becomming something of a SSPX refugee center.
But for all that, they were never quite able to get off the fence, and since 2009, they have been vacillating (e.g., the famous opposition to Bishop Fellay of Fr. Jean; Fr. Jean's exposure of the GREC; etc., only to be seen a short time later touring the USA with the SSPX, or joining in pilgrimages with the SSPX shortly after these little uprisings).
Most recently, they have supported the new marriage guidelines by performing a marriage at a wedding in which the delegation of the diocesan bishop was given to a Capuchin.
I guess you could make an argument either way, but currently they seem to have fallen back into line with the SSPX en masse.