Is it safe to have a lower eyelid lift and a phenol facial peel together?

Yes, it is safe to have a modified phenol croton oil peel and eyelid surgery together. Personally, I do this very frequently.

Lower blepharoplasty and chemical peels are often performed together. It is perfectly safe to do so. You should expect a lot of swelling of the eyelids, especially if the peel is performed on the upper lids. However, this should not interfere with the final result. The cardiac risk from phenol peels depends on the concentration of phenol in the peel solution and rate of application. Since this is one of the most worrisome risks of phenol peels, the physician and anesthesiologist would be well aware of it and take measures to minimize that risk.

It's very important to post a full set of eyelid photographs, and facial photographs to make a determination about how best to proceed to make sure that you're a candidate for both procedures. In our practice, we do not perform full face phenol peels for a variety of reasons

Yes you should be concerned since one of the complications of phenol peels is cardiac issues.
I would offer this in outpatient hospital setting fur anesthesiologist monitoring during and for 1 hour after the operation and peel. I have personally done this in my practice. Expect fees to be in the $8,000+ ranges. Best to virtual consult