misfire code

First: I'm concerned a bit about your compression measurement. If all of your cylinders are less than 100 psi -- there is a serious problem. Minimum specification for compression pressure is 116 psi, maximum is about 175 psi. But 70 is totally unacceptable, as is 90 -95. Consider testing with a different pressure gauge or acquiring assistance to verify you have a valid test result. Replacing a timing chain and cylinder head gasket on this vehicle as a "do it yourself" repair is highly discouraged. At this point, there are far too many variances in what could have occurred to even suggest where to look.