I'm not sure he would have needed permission in 1857 in NSW:
"Until 1823, the legal age in England for marriage was 21 years--for men and women. After 1823, a male could marry as young as fourteen without parental consent, and a girl at 12. Most girls, however, married between the ages of 18 and 23, especially in the upper classes."
The English marriage laws had NO effect in NSW as from 19 July 1823, unless they specifically stated that they were to apply in NSW. This was a ruling by the NSW Chief Justice, Sir Francis Forbes. The date is a significant one, being one day after 18 July 1823, which refers to an English Act for amending laws respecting the solemnization of marriages, 4 Geo IV, c76
I can assure you that if he was not yet 21 years of age, he needed definitely needed permission to marry, but whether the clergy recorded it on the parish register or not is a different matter
https://www.rootschat.com/forum/index.php?topic=648372.0 Re the tickets of leave - two are definitely for Colonial convictions...
The images of the butts for those Tickets of Leave uploaded to Ancestry are actually held by the NSW Archives and you can see their online indexes without charge or needing to access Ancestry.
https://www.records.nsw.gov.au/archives/collections-and-research Ticket of Leave 54/36 (54 being the year, 1854)
Stewart MCDONALD, per the Ganges, and under ‘Remarks’ it reads: District: Goulburn; Tried: Col Bathurst 52. Those remarks indicate that the Ticket of Leave meant that he was allowed to remain in the Goulburn District of NSW and that he was serving a Colonial Sentence after being convicted at Bathurst in 1852,
NOTE this index has his ship of arrival as the GANGES…
Ticket of Leave 55/64 - same name, same ship, same reel at NSW Archives… Remarks … District Brisbane; Tried Bathurst QS 1852, So, allowed to remain in the Brisbane district of (then) NSW, and he had been tried at the Bathurst Quarter Sessions in 1852.
Here is the Keyword Search index. Check for a Stewart McDONALD with an alias in the Deposition Registers too….
https://www.records.nsw.gov.au/archives/collections-and-research/guides-and-indexes/keyname-searchJM