I had the same problem
The 'cure' for me was to drill out the 2 old bolts and replace with slightly longer Grade 8 bolts as identified above.
The drilling through the steel bolts is absolutely the worst and hardest part. I took 2 days to do it with cobalt bits, WD-40 for cooling lube, very slow speeds, and lots and lots of patience. It is a sloooooow process but eventually we drilled all the way through both bolts and then dropped in new ones with appropriate nuts and washers.
2 years later still holding, but boy was that drilling a chore!!!
Hope this helps...there are several threads here on iRV2 about different cures, but this is what I did and I am still satisfied.
2008 Winnebago Journey 39Z DP
Cummins 350hp 6.7L ISB
Towing 2006 Honda CR-V LX