Hi!
Please see a vet; your piggy may need gut stimulants as well as sub-q fluids against dehydration.
Keep in mind that the diarrhea is NOT caused by the fibrous syringe feed (which is actually very much what the gut needs) but by a thoroughly upset gut microbiome not working. Bloating or diarrhea can happen in the wake of a GI stasis, depending on what underlying issues have been causing it.
My Beryn suffered from bloating issues in the wake of a partial or very short full GI stasis even in January; most likely caused by an intense short pain event (sciatica? blood clot?) as she also developed temporary back leg paralysis on the following day. She has made a full recovery.
Please add probiotics to the syringe feed and keep on feeding as much as she will take. If you have a healthy companion, correctly made 'poo soup' (i.e. transfer of live healthy cavy gut microbiome) can also help in addition to the bene bac. You can find more information on that in the links below.
Digestive Disorders: Diarrhea - Bloat - GI Stasis (No Gut Movement) And Not Eating
Complete Syringe Feeding Guide (for amounts and frequency)
Probiotics, Recovery Foods And Vitamin C: Overview With Product Links
All the best! It is always an anxious time with a GI stasis piggy.