I95 is a longer way around for sure haha... Have no idea why I95 bypassed Charleston as big as it is... It also bypasses Myrtle beach...
17 is not connected to Hilton head either as it joins into I95 just north of Hilton Head...
If it were me I would probably make a dry run in my truck first and check the 17 route out. Its not that far away...
Even getting to Myrtle Beach from I95 only has a couple of good less congested routes for big rigs... Going through Conway is the way to go..
I have made a few runs in my truck from Lakewood at Myrtle Beach down that way but always used 17. Also wasn't pulling anything haha... Got family members at both places.
Roy Ken