I changed the hub to be 3925 - lcr, 3926 - tg 1, 3927 - tg2.

the node is 3900 lcr, 3901 tg 1, 3902 tg2.

With some further testing I found that I can dial 3927 which are a pots trunk group and get dial tone and dial out. I dial 3926 which is trunk group 1 (PRI) and it rings and then gives me an recording of invalid number being dialed.