If the meter is attached to a wooden post or a utility pole and then there is underground conduit running the lines into the home's main breaker then those underground lines (and repairs to them) are likely your responsibility. Those were part of the pad infrastructure when the tenant moved in, just like the water and sewer lines, and they're renting that from you as part of the lease.
You need to clearly identify the demarcation for your utility infrastructure provided as part of the lease agreement - for electric commonly everything between the outside meter until the main breaker for the home you have responsibility. And then the utility picks up their responsibility for the utility pole, transformer, etc, but maybe you are responsible for the meter post and the meter loops. Every utility is a little different, but this is a common setup.
In an RV Park you would never see the RV'er digging up the pad to fix a clogged sewer line - that's the Park's responsibility. While an RV Park is not a MHP - the pad infrastructure and responsibilities are similar.