Perhaps it is not Broom's evidence that is outdated but his view of evolution ?
I note that you do not present a real argument from the data to Broom's claims. I can't tell on what basis Broom reached his conclusions.
Some facts to consider.
1) Taxonomy is based very heavily on life as it exists now. If biologists were assembling a taxonomy 30,000,000 years ago it is likely that some of Brooms Orders would not be recognised as such. Because - based on the species extant at that time - it would not be justified. Broom's data may be at least partially explained as a consequence of this.
2) According to the diagram you link to the new Orders have their basis in the aftermath of the K/T mass extinction event. This is a period where we would expect rapid evolution and disversification. Since there as not been another mass extinction event since then we cannot validly compare the data without making allowance for that fact.
How does Broom address these two points ? Does he address them ? If not, then why not ?