What evidence do you have that this British Regiment was especially prone to desertion? One of the main duties of these units of more mature soldiers was to prevent men from the other 19 British Regiments deserting. From 1840, soldiers of 15 years or more service were permitted to volunteer to transfer to Royal Canadian Rifle Regiment and complete their service in Canada. They were allowed to be discharged in Canada, & were permitted 12 women per 100 soldiers rather than the usual 6 per hundred. These conditions were quite an incentive, and initially very favourably received.
As regards the US border area; one Company was at Phillipsburg in autumn of 1842. Then throughout the the rest of the 1840's two Companies were stationed at Isle-aux-Noix. Other Companies joined them in Chambly, etc through to 1869. The nearby Huntingdon area would have been considered a desirable farming location for them soldiers to settle on discharge.